diff --git a/src/Ipunkt/LaravelAnalytics/AnalyticsFacade.php b/src/Ipunkt/LaravelAnalytics/AnalyticsFacade.php
index b4c590e..b338fbc 100644
--- a/src/Ipunkt/LaravelAnalytics/AnalyticsFacade.php
+++ b/src/Ipunkt/LaravelAnalytics/AnalyticsFacade.php
@@ -1,20 +1,23 @@
-<?php namespace Ipunkt\LaravelAnalytics;
+<?php
+
+namespace Ipunkt\LaravelAnalytics;
 
 use Illuminate\Support\Facades\Facade;
 
 /**
  * Class AnalyticsFacade
+ *
  * @package Ipunkt\LaravelAnalytics
  */
 class AnalyticsFacade extends Facade
 {
-	/**
-	 * facade accessor
-	 *
-	 * @return string
-	 */
-	protected static function getFacadeAccessor()
-	{
-		return 'analytics';
-	}
+    /**
+     * facade accessor
+     *
+     * @return string
+     */
+    protected static function getFacadeAccessor()
+    {
+        return 'analytics';
+    }
 }
\ No newline at end of file
diff --git a/src/Ipunkt/LaravelAnalytics/AnalyticsServiceProvider.php b/src/Ipunkt/LaravelAnalytics/AnalyticsServiceProvider.php
index f4ba5bf..3a34619 100644
--- a/src/Ipunkt/LaravelAnalytics/AnalyticsServiceProvider.php
+++ b/src/Ipunkt/LaravelAnalytics/AnalyticsServiceProvider.php
@@ -1,84 +1,86 @@
-<?php namespace Ipunkt\LaravelAnalytics;
+<?php
+
+namespace Ipunkt\LaravelAnalytics;
 
 use Config;
 use Illuminate\Support\ServiceProvider;
 
 class AnalyticsServiceProvider extends ServiceProvider
 {
-	/**
-	 * Indicates if loading of the provider is deferred.
-	 *
-	 * @var bool
-	 */
-	protected $defer = false;
-
-	/**
-	 * Bootstrap the application events.
-	 *
-	 * @return void
-	 */
-	public function boot()
-	{
-		if ($this->isLaravel4()) {
-			$this->package('ipunkt/laravel-analytics');
-
-			return;
-		}
-
-		$config = realpath(__DIR__ . '/../../config/analytics.php');
-
-		$this->mergeConfigFrom($config, 'analytics');
-
-		$this->publishes([
-			$config => config_path('analytics.php'),
-		]);
-	}
-
-	/**
-	 * Register the service provider.
-	 *
-	 * @return void
-	 */
-	public function register()
-	{
-		$packageNamespace = $this->isLaravel4() ? 'laravel-analytics::' : '';
-
-		$this->app->bind('analytics', function () use ($packageNamespace) {
-
-			//	get analytics provider name
-			$provider = Config::get($packageNamespace . 'analytics.provider');
-
-			//	make it a class
-			$providerClass = 'Ipunkt\LaravelAnalytics\Providers\\' . $provider;
-
-			//	getting the config
-			$providerConfig = [];
-			if (Config::has($packageNamespace . 'analytics.configurations.' . $provider)) {
-				$providerConfig = Config::get($packageNamespace . 'analytics.configurations.' . $provider);
-			}
-
-			//	return an instance
-			return new $providerClass($providerConfig);
-		});
-	}
-
-	/**
-	 * Get the services provided by the provider.
-	 *
-	 * @return array
-	 */
-	public function provides()
-	{
-		return array();
-	}
-
-	/**
-	 * are we on laravel 4
-	 *
-	 * @return bool
-	 */
-	private function isLaravel4()
-	{
-		return version_compare(\Illuminate\Foundation\Application::VERSION, '5', '<');
-	}
+    /**
+     * Indicates if loading of the provider is deferred.
+     *
+     * @var bool
+     */
+    protected $defer = false;
+
+    /**
+     * Bootstrap the application events.
+     *
+     * @return void
+     */
+    public function boot()
+    {
+        if ($this->isLaravel4()) {
+            $this->package('ipunkt/laravel-analytics');
+
+            return;
+        }
+
+        $config = realpath(__DIR__ . '/../../config/analytics.php');
+
+        $this->mergeConfigFrom($config, 'analytics');
+
+        $this->publishes([
+            $config => config_path('analytics.php'),
+        ]);
+    }
+
+    /**
+     * Register the service provider.
+     *
+     * @return void
+     */
+    public function register()
+    {
+        $packageNamespace = $this->isLaravel4() ? 'laravel-analytics::' : '';
+
+        $this->app->bind('analytics', function () use ($packageNamespace) {
+
+            //	get analytics provider name
+            $provider = Config::get($packageNamespace . 'analytics.provider');
+
+            //	make it a class
+            $providerClass = 'Ipunkt\LaravelAnalytics\Providers\\' . $provider;
+
+            //	getting the config
+            $providerConfig = [];
+            if (Config::has($packageNamespace . 'analytics.configurations.' . $provider)) {
+                $providerConfig = Config::get($packageNamespace . 'analytics.configurations.' . $provider);
+            }
+
+            //	return an instance
+            return new $providerClass($providerConfig);
+        });
+    }
+
+    /**
+     * Get the services provided by the provider.
+     *
+     * @return array
+     */
+    public function provides()
+    {
+        return [];
+    }
+
+    /**
+     * are we on laravel 4
+     *
+     * @return bool
+     */
+    private function isLaravel4()
+    {
+        return version_compare(\Illuminate\Foundation\Application::VERSION, '5', '<');
+    }
 }
\ No newline at end of file
diff --git a/src/Ipunkt/LaravelAnalytics/Contracts/AnalyticsProviderInterface.php b/src/Ipunkt/LaravelAnalytics/Contracts/AnalyticsProviderInterface.php
index e1e2255..04883d4 100644
--- a/src/Ipunkt/LaravelAnalytics/Contracts/AnalyticsProviderInterface.php
+++ b/src/Ipunkt/LaravelAnalytics/Contracts/AnalyticsProviderInterface.php
@@ -1,4 +1,6 @@
-<?php namespace Ipunkt\LaravelAnalytics\Contracts;
+<?php
+
+namespace Ipunkt\LaravelAnalytics\Contracts;
 
 use Ipunkt\LaravelAnalytics\Data\Campaign;
 use Ipunkt\LaravelAnalytics\Data\Event;
@@ -10,98 +12,116 @@
  */
 interface AnalyticsProviderInterface
 {
-	/**
-	 * returns the javascript code for embedding the analytics stuff
-	 *
-	 * @return string
-	 */
-	public function render();
+    /**
+     * returns the javascript code for embedding the analytics stuff
+     *
+     * @return string
+     */
+    public function render();
+
+    /**
+     * track an page view
+     *
+     * @param null|string $page
+     * @param null|string $title
+     * @param null|string $hittype
+     *
+     * @return void
+     */
+    public function trackPage($page, $title, $hittype);
+
+    /**
+     * track an event
+     *
+     * @param string $category
+     * @param string $action
+     * @param null|string $label
+     * @param null|int $value
+     *
+     * @return void
+     */
+    public function trackEvent($category, $action, $label, $value);
 
-	/**
-	 * track an page view
-	 *
-	 * @param null|string $page
-	 * @param null|string $title
-	 * @param null|string $hittype
-	 *
-	 * @return void
-	 */
-	public function trackPage($page, $title, $hittype);
+    /**
+     * track any custom code
+     *
+     * @param string $customCode
+     *
+     * @return void
+     */
+    public function trackCustom($customCode);
 
-	/**
-	 * track an event
-	 *
-	 * @param string $category
-	 * @param string $action
-	 * @param null|string $label
-	 * @param null|int $value
-	 *
-	 * @return void
-	 */
-	public function trackEvent($category, $action, $label, $value);
+    /**
+     * enable display features
+     *
+     * @return AnalyticsProviderInterface
+     */
+    public function enableDisplayFeatures();
 
-	/**
-	 * track any custom code
-	 *
-	 * @param string $customCode
-	 *
-	 * @return void
-	 */
-	public function trackCustom($customCode);
+    /**
+     * disable display features
+     *
+     * @return AnalyticsProviderInterface
+     */
+    public function disableDisplayFeatures();
 
-	/**
-	 * enable display features
-	 *
-	 * @return AnalyticsProviderInterface
-	 */
-	public function enableDisplayFeatures();
+    /**
+     * enable auto tracking
+     *
+     * @return AnalyticsProviderInterface
+     */
+    public function enableAutoTracking();
 
-	/**
-	 * disable display features
-	 *
-	 * @return AnalyticsProviderInterface
-	 */
-	public function disableDisplayFeatures();
+    /**
+     * disable auto tracking
+     *
+     * @return AnalyticsProviderInterface
+     */
+    public function disableAutoTracking();
 
-	/**
-	 * enable auto tracking
-	 *
-	 * @return AnalyticsProviderInterface
-	 */
-	public function enableAutoTracking();
+    /**
+     * assembles an url for tracking measurement without javascript
+     *
+     * e.g. for tracking email open events within a newsletter
+     *
+     * @param string $metricName
+     * @param mixed $metricValue
+     * @param \Ipunkt\LaravelAnalytics\Data\Event $event
+     * @param \Ipunkt\LaravelAnalytics\Data\Campaign $campaign
+     * @param string|null $clientId
+     * @param array $params
+     *
+     * @return string
+     */
+    public function trackMeasurementUrl($metricName, $metricValue, Event $event, Campaign $campaign, $clientId = null, array $params = []);
 
-	/**
-	 * disable auto tracking
-	 *
-	 * @return AnalyticsProviderInterface
-	 */
-	public function disableAutoTracking();
+    /**
+     * sets or gets nonInteraction
+     *
+     * setting: $this->nonInteraction(true)->render();
+     * getting: if ($this->nonInteraction()) echo 'non-interaction set';
+     *
+     * @param boolean|null $value
+     *
+     * @return bool|AnalyticsProviderInterface
+     */
+    public function nonInteraction($value = null);
 
-	/**
-	 * assembles an url for tracking measurement without javascript
-	 *
-	 * e.g. for tracking email open events within a newsletter
-	 *
-	 * @param string $metricName
-	 * @param mixed $metricValue
-	 * @param \Ipunkt\LaravelAnalytics\Data\Event $event
-	 * @param \Ipunkt\LaravelAnalytics\Data\Campaign $campaign
-	 * @param string|null $clientId
-	 * @param array $params
-	 *
-	 * @return string
-	 */
-	public function trackMeasurementUrl($metricName, $metricValue, Event $event, Campaign $campaign, $clientId = null, array $params = array());
+    /**
+     * sets an user id for user tracking
+     *
+     * @param string $userId
+     *
+     * @return AnalyticsProviderInterface
+     *
+     * @see https://developers.google.com/analytics/devguides/collection/analyticsjs/cookies-user-id
+     */
+    public function setUserId($userId);
 
-	/**
-	 * sets or gets nonInteraction
-	 *
-	 * setting: $this->nonInteraction(true)->render();
-	 * getting: if ($this->nonInteraction()) echo 'non-interaction set';
-	 *
-	 * @param boolean|null $value
-	 *
-	 * @return bool|AnalyticsProviderInterface
-	 */
-	public function nonInteraction($value = null);
+    /**
+     * unsets a possible given user id
+     *
+     * @return AnalyticsProviderInterface
+     */
+    public function unsetUserId();
 }
\ No newline at end of file
diff --git a/src/Ipunkt/LaravelAnalytics/Contracts/TrackingBagInterface.php b/src/Ipunkt/LaravelAnalytics/Contracts/TrackingBagInterface.php
index f765332..1bc2377 100644
--- a/src/Ipunkt/LaravelAnalytics/Contracts/TrackingBagInterface.php
+++ b/src/Ipunkt/LaravelAnalytics/Contracts/TrackingBagInterface.php
@@ -1,24 +1,27 @@
-<?php namespace Ipunkt\LaravelAnalytics\Contracts;
+<?php
+
+namespace Ipunkt\LaravelAnalytics\Contracts;
 
 /**
  * Interface TrackingBagInterface
+ *
  * @package Ipunkt\LaravelAnalytics\Contracts
  */
 interface TrackingBagInterface
 {
-	/**
-	 * adds a tracking
-	 *
-	 * @param string $tracking
-	 *
-	 * @return void
-	 */
-	public function add($tracking);
+    /**
+     * adds a tracking
+     *
+     * @param string $tracking
+     *
+     * @return void
+     */
+    public function add($tracking);
 
-	/**
-	 * returns all trackings
-	 *
-	 * @return array
-	 */
-	public function get();
+    /**
+     * returns all trackings
+     *
+     * @return array
+     */
+    public function get();
 }
\ No newline at end of file
diff --git a/src/Ipunkt/LaravelAnalytics/Data/Campaign.php b/src/Ipunkt/LaravelAnalytics/Data/Campaign.php
index 5eb1902..1bc6cd2 100644
--- a/src/Ipunkt/LaravelAnalytics/Data/Campaign.php
+++ b/src/Ipunkt/LaravelAnalytics/Data/Campaign.php
@@ -1,103 +1,106 @@
-<?php namespace Ipunkt\LaravelAnalytics\Data;
+<?php
+
+namespace Ipunkt\LaravelAnalytics\Data;
 
 /**
  * Class Campaign
+ *
  * @package Ipunkt\LaravelAnalytics\Data
  */
 class Campaign
 {
-	/**
-	 * campaign source
-	 *
-	 * @var string
-	 */
-	private $source = 'newsletter';
+    /**
+     * campaign source
+     *
+     * @var string
+     */
+    private $source = 'newsletter';
 
-	/**
-	 * campaign medium
-	 *
-	 * @var string
-	 */
-	private $medium = 'email';
+    /**
+     * campaign medium
+     *
+     * @var string
+     */
+    private $medium = 'email';
 
-	/**
-	 * campaign name
-	 *
-	 * @var string
-	 */
-	private $name;
+    /**
+     * campaign name
+     *
+     * @var string
+     */
+    private $name;
 
-	/**
-	 * @param string $name
-	 */
-	public function __construct($name = '')
-	{
-		$this->name = $name;
-	}
+    /**
+     * @param string $name
+     */
+    public function __construct($name = '')
+    {
+        $this->name = $name;
+    }
 
-	/**
-	 * set medium
-	 *
-	 * @param string $medium
-	 *
-	 * @return Campaign
-	 */
-	public function setMedium($medium)
-	{
-		$this->medium = $medium;
+    /**
+     * set medium
+     *
+     * @param string $medium
+     *
+     * @return Campaign
+     */
+    public function setMedium($medium)
+    {
+        $this->medium = $medium;
 
-		return $this;
-	}
+        return $this;
+    }
 
-	/**
-	 * @return string
-	 */
-	public function getMedium()
-	{
-		return $this->medium;
-	}
+    /**
+     * @return string
+     */
+    public function getMedium()
+    {
+        return $this->medium;
+    }
 
-	/**
-	 * set name
-	 *
-	 * @param string $name
-	 *
-	 * @return Campaign
-	 */
-	public function setName($name)
-	{
-		$this->name = $name;
+    /**
+     * set name
+     *
+     * @param string $name
+     *
+     * @return Campaign
+     */
+    public function setName($name)
+    {
+        $this->name = $name;
 
-		return $this;
-	}
+        return $this;
+    }
 
-	/**
-	 * @return string
-	 */
-	public function getName()
-	{
-		return $this->name;
-	}
+    /**
+     * @return string
+     */
+    public function getName()
+    {
+        return $this->name;
+    }
 
-	/**
-	 * set source
-	 *
-	 * @param string $source
-	 *
-	 * @return Campaign
-	 */
-	public function setSource($source)
-	{
-		$this->source = $source;
+    /**
+     * set source
+     *
+     * @param string $source
+     *
+     * @return Campaign
+     */
+    public function setSource($source)
+    {
+        $this->source = $source;
 
-		return $this;
-	}
+        return $this;
+    }
 
-	/**
-	 * @return string
-	 */
-	public function getSource()
-	{
-		return $this->source;
-	}
+    /**
+     * @return string
+     */
+    public function getSource()
+    {
+        return $this->source;
+    }
 }
\ No newline at end of file
diff --git a/src/Ipunkt/LaravelAnalytics/Data/Event.php b/src/Ipunkt/LaravelAnalytics/Data/Event.php
index f89bdce..bb48401 100644
--- a/src/Ipunkt/LaravelAnalytics/Data/Event.php
+++ b/src/Ipunkt/LaravelAnalytics/Data/Event.php
@@ -1,124 +1,135 @@
-<?php namespace Ipunkt\LaravelAnalytics\Data;
+<?php
+
+namespace Ipunkt\LaravelAnalytics\Data;
 
 /**
  * Class Event
+ *
  * @package Ipunkt\LaravelAnalytics\Data
  */
 class Event
 {
-	/**
-	 * event category
-	 *
-	 * @var string
-	 */
-	private $category = 'email';
-
-	/**
-	 * event action
-	 *
-	 * @var string
-	 */
-	private $action = 'open';
-
-	/**
-	 * event label
-	 *
-	 * @var string
-	 */
-	private $label;
-
-	/**
-	 * hit type
-	 *
-	 * @var string
-	 */
-	private $hitType = 'event';
-
-	/**
-	 * set action
-	 *
-	 * @param string $action
-	 *
-	 * @return Event
-	 */
-	public function setAction($action)
-	{
-		$this->action = $action;
-
-		return $this;
-	}
-
-	/**
-	 * @return string
-	 */
-	public function getAction()
-	{
-		return $this->action;
-	}
-
-	/**
-	 * set category
-	 *
-	 * @param string $category
-	 *
-	 * @return Event
-	 */
-	public function setCategory($category)
-	{
-		$this->category = $category;
-
-		return $this;
-	}
-
-	/**
-	 * @return string
-	 */
-	public function getCategory()
-	{
-		return $this->category;
-	}
-
-	/**
-	 * set hitType
-	 *
-	 * @param string $hitType
-	 *
-	 * @return Event
-	 */
-	public function setHitType($hitType)
-	{
-		$this->hitType = $hitType;
-
-		return $this;
-	}
-
-	/**
-	 * @return string
-	 */
-	public function getHitType()
-	{
-		return $this->hitType;
-	}
-
-	/**
-	 * set label
-	 *
-	 * @param string $label
-	 *
-	 * @return Event
-	 */
-	public function setLabel($label)
-	{
-		$this->label = $label;
-
-		return $this;
-	}
-
-	/**
-	 * @return string
-	 */
-	public function getLabel()
-	{
-		return $this->label;
-	}
+    /**
+     * event category
+     *
+     * @var string
+     */
+    private $category = 'email';
+
+    /**
+     * event action
+     *
+     * @var string
+     */
+    private $action = 'open';
+
+    /**
+     * event label
+     *
+     * @var string
+     */
+    private $label;
+
+    /**
+     * hit type
+     *
+     * @var string
+     */
+    private $hitType = 'event';
+
+    /**
+     * set action
+     *
+     * @param string $action
+     *
+     * @return Event
+     */
+    public function setAction($action)
+    {
+        $this->action = $action;
+
+        return $this;
+    }
+
+    /**
+     * returns action
+     *
+     * @return string
+     */
+    public function getAction()
+    {
+        return $this->action;
+    }
+
+    /**
+     * set category
+     *
+     * @param string $category
+     *
+     * @return Event
+     */
+    public function setCategory($category)
+    {
+        $this->category = $category;
+
+        return $this;
+    }
+
+    /**
+     * returns category
+     *
+     * @return string
+     */
+    public function getCategory()
+    {
+        return $this->category;
+    }
+
+    /**
+     * sets hit type
+     *
+     * @param string $hitType
+     *
+     * @return Event
+     */
+    public function setHitType($hitType)
+    {
+        $this->hitType = $hitType;
+
+        return $this;
+    }
+
+    /**
+     * returns hit type
+     *
+     * @return string
+     */
+    public function getHitType()
+    {
+        return $this->hitType;
+    }
+
+    /**
+     * sets label
+     *
+     * @param string $label
+     *
+     * @return Event
+     */
+    public function setLabel($label)
+    {
+        $this->label = $label;
+
+        return $this;
+    }
+
+    /**
+     * returns label
+     *
+     * @return string
+     */
+    public function getLabel()
+    {
+        return $this->label;
+    }
 }
\ No newline at end of file
diff --git a/src/Ipunkt/LaravelAnalytics/Providers/GoogleAnalytics.php b/src/Ipunkt/LaravelAnalytics/Providers/GoogleAnalytics.php
index 06dacf0..a2f4459 100644
--- a/src/Ipunkt/LaravelAnalytics/Providers/GoogleAnalytics.php
+++ b/src/Ipunkt/LaravelAnalytics/Providers/GoogleAnalytics.php
@@ -1,4 +1,6 @@
-<?php namespace Ipunkt\LaravelAnalytics\Providers;
+<?php
+
+namespace Ipunkt\LaravelAnalytics\Providers;
 
 use InvalidArgumentException;
 use Ipunkt\LaravelAnalytics\Contracts\AnalyticsProviderInterface;
@@ -14,374 +16,419 @@
  */
 class GoogleAnalytics implements AnalyticsProviderInterface
 {
-	/**
-	 * tracking id
-	 *
-	 * @var string
-	 */
-	private $trackingId;
-
-	/**
-	 * tracking domain
-	 *
-	 * @var string
-	 */
-	private $trackingDomain;
-
-	/**
-	 * display features plugin enabled or disabled
-	 *
-	 * @var bool
-	 */
-	private $displayFeatures = false;
-
-	/**
-	 * anonymize users ip
-	 *
-	 * @var bool
-	 */
-	private $anonymizeIp = false;
-
-	/**
-	 * auto tracking the page view
-	 *
-	 * @var bool
-	 */
-	private $autoTrack = false;
-
-	/**
-	 * debug mode
-	 *
-	 * @var bool
-	 */
-	private $debug = false;
-
-	/**
-	 * for event tracking it can mark track as non-interactive so the bounce-rate calculation ignores that tracking
-	 *
-	 * @var bool
-	 */
-	private $nonInteraction = false;
-
-	/**
-	 * session tracking bag
-	 *
-	 * @var TrackingBag
-	 */
-	private $trackingBag;
-
-	/**
-	 * use https for the tracking measurement url
-	 *
-	 * @var bool
-	 */
-	private $secureTrackingUrl = true;
-
-	/**
-	 * setting options via constructor
-	 *
-	 * @param array $options
-	 *
-	 * @throws InvalidArgumentException when tracking id not set
-	 */
-	public function __construct(array $options = array())
-	{
-		$this->trackingId = array_get($options, 'tracking_id');
-		$this->trackingDomain = array_get($options, 'tracking_domain', 'auto');
-		$this->displayFeatures = array_get($options, 'display_features', false);
-		$this->anonymizeIp = array_get($options, 'anonymize_ip', false);
-		$this->autoTrack = array_get($options, 'auto_track', false);
-		$this->debug = array_get($options, 'debug', false);
-
-		if ($this->trackingId === null) {
-			throw new InvalidArgumentException('Argument tracking_id can not be null');
-		}
-
-		$this->trackingBag = new TrackingBag;
-	}
-
-	/**
-	 * track an page view
-	 *
-	 * @param null|string $page
-	 * @param null|string $title
-	 * @param null|string $hittype
-	 *
-	 * @return void
-	 */
-	public function trackPage($page = null, $title = null, $hittype = null)
-	{
-		$allowedHitTypes = ['pageview', 'appview', 'event', 'transaction', 'item', 'social', 'exception', 'timing'];
-		if ($hittype === null) {
-			$hittype = $allowedHitTypes[0];
-		}
-
-		if ( ! in_array($hittype, $allowedHitTypes)) {
-			return;
-		}
-
-		$trackingCode = "ga('send', 'pageview');";
-
-		if ($page !== null || $title !== null || $hittype !== null) {
-			$page = ($page === null) ? "window.location.protocol + '//' + window.location.hostname + window.location.pathname + window.location.search" : "'{$page}'";
-			$title = ($title === null) ? "document.title" : "'{$title}'";
-
-			$trackingCode = "ga('send', {'hitType': '{$hittype}', 'page': {$page}, 'title': '{$title}'});";
-		}
-
-		$this->trackingBag->add($trackingCode);
-	}
-
-	/**
-	 * track an event
-	 *
-	 * @param string $category
-	 * @param string $action
-	 * @param null|string $label
-	 * @param null|int $value
-	 */
-	public function trackEvent($category, $action, $label = null, $value = null)
-	{
-		$command = '';
-		if ($label !== null) {
-			$command .= ", '{$label}'";
-			if ($value !== null && is_numeric($value)) {
-				$command .= ", {$value}";
-			}
-		}
-
-		$trackingCode = "ga('send', 'event', '{$category}', '{$action}'$command);";
-
-		$this->trackingBag->add($trackingCode);
-	}
-
-	/**
-	 * track any custom code
-	 *
-	 * @param string $customCode
-	 *
-	 * @return void
-	 */
-	public function trackCustom($customCode)
-	{
-		$this->trackingBag->add($customCode);
-	}
-
-	/**
-	 * enable display features
-	 *
-	 * @return GoogleAnalytics
-	 */
-	public function enableDisplayFeatures()
-	{
-		$this->displayFeatures = true;
-
-		return $this;
-	}
-
-	/**
-	 * disable display features
-	 *
-	 * @return GoogleAnalytics
-	 */
-	public function disableDisplayFeatures()
-	{
-		$this->displayFeatures = false;
-
-		return $this;
-	}
-
-	/**
-	 * enable auto tracking
-	 *
-	 * @return GoogleAnalytics
-	 */
-	public function enableAutoTracking()
-	{
-		$this->autoTrack = true;
-
-		return $this;
-	}
-
-	/**
-	 * disable auto tracking
-	 *
-	 * @return GoogleAnalytics
-	 */
-	public function disableAutoTracking()
-	{
-		$this->autoTrack = false;
-
-		return $this;
-	}
-
-	/**
-	 * returns the javascript embedding code
-	 *
-	 * @return string
-	 */
-	public function render()
-	{
-		$script[] = $this->_getJavascriptTemplateBlockBegin();
-
-		if ($this->debug || App::environment('local')) {
-			$script[] = "ga('create', '{$this->trackingId}', { 'cookieDomain': 'none' });";
-		} else {
-			$script[] = "ga('create', '{$this->trackingId}', '{$this->trackingDomain}');";
-		}
-
-		if ($this->displayFeatures) {
-			$script[] = "ga('require', 'displayfeatures');";
-		}
-
-		if ($this->anonymizeIp) {
-			$script[] = "ga('set', 'anonymizeIp', true);";
-		}
-
-		if ($this->nonInteraction) {
-			$script[] = "ga('set', 'nonInteraction', true);";
-		}
-
-		$trackingStack = $this->trackingBag->get();
-		if (count($trackingStack)) {
-			$script[] = implode("\n", $trackingStack);
-		}
-
-		if ($this->autoTrack) {
-			$script[] = "ga('send', 'pageview');";
-		}
-		$script[] = $this->_getJavascriptTemplateBlockEnd();
-
-		return implode('', $script);
-	}
-
-	/**
-	 * sets or gets nonInteraction
-	 *
-	 * setting: $this->nonInteraction(true)->render();
-	 * getting: if ($this->nonInteraction()) echo 'non-interaction set';
-	 *
-	 * @param boolean|null $value
-	 *
-	 * @return bool|$this
-	 */
-	public function nonInteraction($value = null)
-	{
-		if (null === $value) {
-			return $this->nonInteraction;
-		}
-
-		$this->nonInteraction = ($value === true);
-
-		return $this;
-	}
-
-	/**
-	 * returns start block
-	 *
-	 * @return string
-	 */
-	protected function _getJavascriptTemplateBlockBegin()
-	{
-		$appendix = $this->debug ? '_debug' : '';
-
-		return "<script>(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)})(window,document,'script','//www.google-analytics.com/analytics{$appendix}.js','ga');";
-	}
-
-	/**
-	 * returns end block
-	 *
-	 * @return string
-	 */
-	protected function _getJavascriptTemplateBlockEnd()
-	{
-		return '</script>';
-	}
-
-	/**
-	 * make the tracking measurement url unsecure
-	 *
-	 * @return $this
-	 */
-	public function unsecureMeasurementUrl()
-	{
-		$this->secureTrackingUrl = false;
-
-		return $this;
-	}
-
-	/**
-	 * use the secured version of the tracking measurement url
-	 *
-	 * @return $this
-	 */
-	public function secureMeasurementUrl()
-	{
-		$this->secureTrackingUrl = false;
-
-		return $this;
-	}
-
-	/**
-	 * assembles an url for tracking measurement without javascript
-	 *
-	 * e.g. for tracking email open events within a newsletter
-	 *
-	 * @param string $metricName
-	 * @param mixed $metricValue
-	 * @param \Ipunkt\LaravelAnalytics\Data\Event $event
-	 * @param \Ipunkt\LaravelAnalytics\Data\Campaign $campaign
-	 * @param string|null $clientId
-	 * @param array $params
-	 *
-	 * @return string
-	 *
-	 * @experimental
-	 */
-	public function trackMeasurementUrl($metricName, $metricValue, Event $event, Campaign $campaign, $clientId = null, array $params = array())
-	{
-		$uniqueId = ($clientId !== null) ? $clientId : uniqid('track_');
-
-		if ($event->getLabel() === '') {
-			$event->setLabel($uniqueId);
-		}
-
-		if ($campaign->getName() === '') {
-			$campaign->setName('Campaign ' . date('Y-m-d'));
-		}
-
-		$protocol = $this->secureTrackingUrl ? 'https' : 'http';
-
-		$defaults = [
-			'url' => $protocol . '://www.google-analytics.com/collect?',
-			'params' => [
-				'v' => 1,    //	protocol version
-				'tid' => $this->trackingId,    //	tracking id
-				'cid' => $uniqueId,    //	client id
-				't' => $event->getHitType(),
-				'ec' => $event->getCategory(),
-				'ea' => $event->getAction(),
-				'el' => $event->getLabel(),
-				'cs' => $campaign->getSource(),
-				'cm' => $campaign->getMedium(),
-				'cn' => $campaign->getName(),
-				$metricName => $metricValue,    //	metric data
-			],
-		];
-
-		$url = isset($params['url']) ? $params['url'] : $defaults['url'];
-		$url = rtrim($url, '?') . '?';
-
-		if (isset($params['url']))
-			unset($params['url']);
-
-		$params = array_merge($defaults['params'], $params);
-		$queryParams = [];
-		foreach ($params as $key => $value) {
-			if ( ! empty($value))
-				$queryParams[] = sprintf('%s=%s', $key, $value);
-		}
-
-		return $url . implode('&', $queryParams);
-	}
+    /**
+     * tracking id
+     *
+     * @var string
+     */
+    private $trackingId;
+
+    /**
+     * tracking domain
+     *
+     * @var string
+     */
+    private $trackingDomain;
+
+    /**
+     * display features plugin enabled or disabled
+     *
+     * @var bool
+     */
+    private $displayFeatures = false;
+
+    /**
+     * anonymize users ip
+     *
+     * @var bool
+     */
+    private $anonymizeIp = false;
+
+    /**
+     * auto tracking the page view
+     *
+     * @var bool
+     */
+    private $autoTrack = false;
+
+    /**
+     * debug mode
+     *
+     * @var bool
+     */
+    private $debug = false;
+
+    /**
+     * for event tracking it can mark track as non-interactive so the bounce-rate calculation ignores that tracking
+     *
+     * @var bool
+     */
+    private $nonInteraction = false;
+
+    /**
+     * session tracking bag
+     *
+     * @var TrackingBag
+     */
+    private $trackingBag;
+
+    /**
+     * use https for the tracking measurement url
+     *
+     * @var bool
+     */
+    private $secureTrackingUrl = true;
+
+    /**
+     * a user id for tracking
+     *
+     * @var string|null
+     */
+    private $userId = null;
+
+    /**
+     * setting options via constructor
+     *
+     * @param array $options
+     *
+     * @throws InvalidArgumentException when tracking id not set
+     */
+    public function __construct(array $options = [])
+    {
+        $this->trackingId = array_get($options, 'tracking_id');
+        $this->trackingDomain = array_get($options, 'tracking_domain', 'auto');
+        $this->displayFeatures = array_get($options, 'display_features', false);
+        $this->anonymizeIp = array_get($options, 'anonymize_ip', false);
+        $this->autoTrack = array_get($options, 'auto_track', false);
+        $this->debug = array_get($options, 'debug', false);
+
+        if ($this->trackingId === null) {
+            throw new InvalidArgumentException('Argument tracking_id can not be null');
+        }
+
+        $this->trackingBag = new TrackingBag;
+    }
+
+    /**
+     * track an page view
+     *
+     * @param null|string $page
+     * @param null|string $title
+     * @param null|string $hittype
+     *
+     * @return void
+     */
+    public function trackPage($page = null, $title = null, $hittype = null)
+    {
+        $allowedHitTypes = ['pageview', 'appview', 'event', 'transaction', 'item', 'social', 'exception', 'timing'];
+        if ($hittype === null) {
+            $hittype = $allowedHitTypes[0];
+        }
+
+        if ( ! in_array($hittype, $allowedHitTypes)) {
+            return;
+        }
+
+        $trackingCode = "ga('send', 'pageview');";
+
+        if ($page !== null || $title !== null || $hittype !== null) {
+            $page = ($page === null) ? "window.location.protocol + '//' + window.location.hostname + window.location.pathname + window.location.search" : "'{$page}'";
+            $title = ($title === null) ? "document.title" : "'{$title}'";
+
+            $trackingCode = "ga('send', {'hitType': '{$hittype}', 'page': {$page}, 'title': '{$title}'});";
+        }
+
+        $this->trackingBag->add($trackingCode);
+    }
+
+    /**
+     * track an event
+     *
+     * @param string $category
+     * @param string $action
+     * @param null|string $label
+     * @param null|int $value
+     */
+    public function trackEvent($category, $action, $label = null, $value = null)
+    {
+        $command = '';
+        if ($label !== null) {
+            $command .= ", '{$label}'";
+            if ($value !== null && is_numeric($value)) {
+                $command .= ", {$value}";
+            }
+        }
+
+        $trackingCode = "ga('send', 'event', '{$category}', '{$action}'$command);";
+
+        $this->trackingBag->add($trackingCode);
+    }
+
+    /**
+     * track any custom code
+     *
+     * @param string $customCode
+     *
+     * @return void
+     */
+    public function trackCustom($customCode)
+    {
+        $this->trackingBag->add($customCode);
+    }
+
+    /**
+     * enable display features
+     *
+     * @return GoogleAnalytics
+     */
+    public function enableDisplayFeatures()
+    {
+        $this->displayFeatures = true;
+
+        return $this;
+    }
+
+    /**
+     * disable display features
+     *
+     * @return GoogleAnalytics
+     */
+    public function disableDisplayFeatures()
+    {
+        $this->displayFeatures = false;
+
+        return $this;
+    }
+
+    /**
+     * enable auto tracking
+     *
+     * @return GoogleAnalytics
+     */
+    public function enableAutoTracking()
+    {
+        $this->autoTrack = true;
+
+        return $this;
+    }
+
+    /**
+     * disable auto tracking
+     *
+     * @return GoogleAnalytics
+     */
+    public function disableAutoTracking()
+    {
+        $this->autoTrack = false;
+
+        return $this;
+    }
+
+    /**
+     * returns the javascript embedding code
+     *
+     * @return string
+     */
+    public function render()
+    {
+        $script[] = $this->_getJavascriptTemplateBlockBegin();
+
+        $trackingUserId = (null === $this->userId)
+            ? ''
+            : sprintf(", {'userId': '%s'}", $this->userId);
+
+        if ($this->debug || App::environment('local')) {
+            $script[] = "ga('create', '{$this->trackingId}', { 'cookieDomain': 'none' }{$trackingUserId});";
+        } else {
+            $script[] = "ga('create', '{$this->trackingId}', '{$this->trackingDomain}'{$trackingUserId});";
+        }
+
+        if ($this->displayFeatures) {
+            $script[] = "ga('require', 'displayfeatures');";
+        }
+
+        if ($this->anonymizeIp) {
+            $script[] = "ga('set', 'anonymizeIp', true);";
+        }
+
+        if ($this->nonInteraction) {
+            $script[] = "ga('set', 'nonInteraction', true);";
+        }
+
+        $trackingStack = $this->trackingBag->get();
+        if (count($trackingStack)) {
+            $script[] = implode("\n", $trackingStack);
+        }
+
+        if ($this->autoTrack) {
+            $script[] = "ga('send', 'pageview');";
+        }
+        $script[] = $this->_getJavascriptTemplateBlockEnd();
+
+        return implode('', $script);
+    }
+
+    /**
+     * sets or gets nonInteraction
+     *
+     * setting: $this->nonInteraction(true)->render();
+     * getting: if ($this->nonInteraction()) echo 'non-interaction set';
+     *
+     * @param boolean|null $value
+     *
+     * @return bool|$this
+     */
+    public function nonInteraction($value = null)
+    {
+        if (null === $value) {
+            return $this->nonInteraction;
+        }
+
+        $this->nonInteraction = ($value === true);
+
+        return $this;
+    }
+
+    /**
+     * returns start block
+     *
+     * @return string
+     */
+    protected function _getJavascriptTemplateBlockBegin()
+    {
+        $appendix = $this->debug ? '_debug' : '';
+
+        return "<script>(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)})(window,document,'script','//www.google-analytics.com/analytics{$appendix}.js','ga');";
+    }
+
+    /**
+     * returns end block
+     *
+     * @return string
+     */
+    protected function _getJavascriptTemplateBlockEnd()
+    {
+        return '</script>';
+    }
+
+    /**
+     * make the tracking measurement url unsecure
+     *
+     * @return $this
+     */
+    public function unsecureMeasurementUrl()
+    {
+        $this->secureTrackingUrl = false;
+
+        return $this;
+    }
+
+    /**
+     * use the secured version of the tracking measurement url
+     *
+     * @return $this
+     */
+    public function secureMeasurementUrl()
+    {
+        $this->secureTrackingUrl = false;
+
+        return $this;
+    }
+
+    /**
+     * assembles an url for tracking measurement without javascript
+     *
+     * e.g. for tracking email open events within a newsletter
+     *
+     * @param string $metricName
+     * @param mixed $metricValue
+     * @param \Ipunkt\LaravelAnalytics\Data\Event $event
+     * @param \Ipunkt\LaravelAnalytics\Data\Campaign $campaign
+     * @param string|null $clientId
+     * @param array $params
+     *
+     * @return string
+     *
+     * @experimental
+     */
+    public function trackMeasurementUrl(
+        $metricName,
+        $metricValue,
+        Event $event,
+        Campaign $campaign,
+        $clientId = null,
+        array $params = []
+    ) {
+        $uniqueId = ($clientId !== null) ? $clientId : uniqid('track_');
+
+        if ($event->getLabel() === '') {
+            $event->setLabel($uniqueId);
+        }
+
+        if ($campaign->getName() === '') {
+            $campaign->setName('Campaign ' . date('Y-m-d'));
+        }
+
+        $protocol = $this->secureTrackingUrl ? 'https' : 'http';
+
+        $defaults = [
+            'url' => $protocol . '://www.google-analytics.com/collect?',
+            'params' => [
+                'v' => 1,    //	protocol version
+                'tid' => $this->trackingId,    //	tracking id
+                'cid' => $uniqueId,    //	client id
+                't' => $event->getHitType(),
+                'ec' => $event->getCategory(),
+                'ea' => $event->getAction(),
+                'el' => $event->getLabel(),
+                'cs' => $campaign->getSource(),
+                'cm' => $campaign->getMedium(),
+                'cn' => $campaign->getName(),
+                $metricName => $metricValue,    //	metric data
+            ],
+        ];
+
+        $url = isset($params['url']) ? $params['url'] : $defaults['url'];
+        $url = rtrim($url, '?') . '?';
+
+        if (isset($params['url'])) {
+            unset($params['url']);
+        }
+
+        $params = array_merge($defaults['params'], $params);
+        $queryParams = [];
+        foreach ($params as $key => $value) {
+            if ( ! empty($value)) {
+                $queryParams[] = sprintf('%s=%s', $key, $value);
+            }
+        }
+
+        return $url . implode('&', $queryParams);
+    }
+
+    /**
+     * sets an user id for user tracking
+     *
+     * @param string $userId
+     *
+     * @return AnalyticsProviderInterface
+     *
+     * @see https://developers.google.com/analytics/devguides/collection/analyticsjs/cookies-user-id
+     */
+    public function setUserId($userId)
+    {
+        $this->userId = $userId;
+
+        return $this;
+    }
+
+    /**
+     * unsets a possible given user id
+     *
+     * @return AnalyticsProviderInterface
+     */
+    public function unsetUserId()
+    {
+        return $this->setUserId(null);
+    }
 }
\ No newline at end of file
diff --git a/src/Ipunkt/LaravelAnalytics/Providers/NoAnalytics.php b/src/Ipunkt/LaravelAnalytics/Providers/NoAnalytics.php
index c055a59..140aaf0 100644
--- a/src/Ipunkt/LaravelAnalytics/Providers/NoAnalytics.php
+++ b/src/Ipunkt/LaravelAnalytics/Providers/NoAnalytics.php
@@ -1,4 +1,6 @@
-<?php namespace Ipunkt\LaravelAnalytics\Providers;
+<?php
+
+namespace Ipunkt\LaravelAnalytics\Providers;
 
 use Ipunkt\LaravelAnalytics\Contracts\AnalyticsProviderInterface;
 use Ipunkt\LaravelAnalytics\Data\Campaign;
@@ -11,128 +13,159 @@
  */
 class NoAnalytics implements AnalyticsProviderInterface
 {
-	/**
-	 * returns the javascript code for embedding the analytics stuff
-	 *
-	 * @return string
-	 */
-	public function render()
-	{
-		return '';
-	}
+    /**
+     * returns the javascript code for embedding the analytics stuff
+     *
+     * @return string
+     */
+    public function render()
+    {
+        return '';
+    }
+
+    /**
+     * track an page view
+     *
+     * @param null|string $page
+     * @param null|string $title
+     * @param null|string $hittype
+     *
+     * @return void
+     */
+    public function trackPage($page, $title, $hittype)
+    {
+    }
+
+    /**
+     * track an event
+     *
+     * @param string $category
+     * @param string $action
+     * @param null|string $label
+     * @param null|int $value
+     *
+     * @return void
+     */
+    public function trackEvent($category, $action, $label, $value)
+    {
+    }
 
-	/**
-	 * track an page view
-	 *
-	 * @param null|string $page
-	 * @param null|string $title
-	 * @param null|string $hittype
-	 *
-	 * @return void
-	 */
-	public function trackPage($page, $title, $hittype)
-	{
-	}
+    /**
+     * track any custom code
+     *
+     * @param string $customCode
+     *
+     * @return void
+     */
+    public function trackCustom($customCode)
+    {
+    }
 
-	/**
-	 * track an event
-	 *
-	 * @param string $category
-	 * @param string $action
-	 * @param null|string $label
-	 * @param null|int $value
-	 *
-	 * @return void
-	 */
-	public function trackEvent($category, $action, $label, $value)
-	{
-	}
+    /**
+     * enable display features
+     *
+     * @return NoAnalytics
+     */
+    public function enableDisplayFeatures()
+    {
+        return $this;
+    }
 
-	/**
-	 * track any custom code
-	 *
-	 * @param string $customCode
-	 *
-	 * @return void
-	 */
-	public function trackCustom($customCode)
-	{
-	}
+    /**
+     * disable display features
+     *
+     * @return NoAnalytics
+     */
+    public function disableDisplayFeatures()
+    {
+        return $this;
+    }
 
-	/**
-	 * enable display features
-	 *
-	 * @return NoAnalytics
-	 */
-	public function enableDisplayFeatures()
-	{
-		return $this;
-	}
+    /**
+     * enable auto tracking
+     *
+     * @return NoAnalytics
+     */
+    public function enableAutoTracking()
+    {
+        return $this;
+    }
 
-	/**
-	 * disable display features
-	 *
-	 * @return NoAnalytics
-	 */
-	public function disableDisplayFeatures()
-	{
-		return $this;
-	}
+    /**
+     * disable auto tracking
+     *
+     * @return NoAnalytics
+     */
+    public function disableAutoTracking()
+    {
+        return $this;
+    }
 
-	/**
-	 * enable auto tracking
-	 *
-	 * @return NoAnalytics
-	 */
-	public function enableAutoTracking()
-	{
-		return $this;
-	}
+    /**
+     * assembles an url for tracking measurement without javascript
+     *
+     * e.g. for tracking email open events within a newsletter
+     *
+     * @param string $metricName
+     * @param mixed $metricValue
+     * @param \Ipunkt\LaravelAnalytics\Data\Event $event
+     * @param \Ipunkt\LaravelAnalytics\Data\Campaign $campaign
+     * @param string|null $clientId
+     * @param array $params
+     *
+     * @return string
+     */
+    public function trackMeasurementUrl(
+        $metricName,
+        $metricValue,
+        Event $event,
+        Campaign $campaign,
+        $clientId = null,
+        array $params = []
+    ) {
+        return '';
+    }
 
-	/**
-	 * disable auto tracking
-	 *
-	 * @return NoAnalytics
-	 */
-	public function disableAutoTracking()
-	{
-		return $this;
-	}
+    /**
+     * sets or gets nonInteraction
+     *
+     * setting: $this->nonInteraction(true)->render();
+     * getting: if ($this->nonInteraction()) echo 'non-interaction set';
+     *
+     * @param boolean|null $value
+     *
+     * @return bool|AnalyticsProviderInterface
+     */
+    public function nonInteraction($value = null)
+    {
+        if (null === $value) {
+            return false;
+        }
 
-	/**
-	 * assembles an url for tracking measurement without javascript
-	 *
-	 * e.g. for tracking email open events within a newsletter
-	 *
-	 * @param string $metricName
-	 * @param mixed $metricValue
-	 * @param \Ipunkt\LaravelAnalytics\Data\Event $event
-	 * @param \Ipunkt\LaravelAnalytics\Data\Campaign $campaign
-	 * @param string|null $clientId
-	 * @param array $params
-	 *
-	 * @return string
-	 */
-	public function trackMeasurementUrl($metricName, $metricValue, Event $event, Campaign $campaign, $clientId = null, array $params = array())
-	{
-		return '';
-	}
+        return $this;
+    }
 
-	/**
-	 * sets or gets nonInteraction
-	 *
-	 * setting: $this->nonInteraction(true)->render();
-	 * getting: if ($this->nonInteraction()) echo 'non-interaction set';
-	 *
-	 * @param boolean|null $value
-	 *
-	 * @return bool|AnalyticsProviderInterface
-	 */
-	public function nonInteraction($value = null)
-	{
-		if (null === $value)
-			return false;
+    /**
+     * sets an user id for user tracking
+     *
+     * @param string $userId
+     *
+     * @return AnalyticsProviderInterface
+     *
+     * @see https://developers.google.com/analytics/devguides/collection/analyticsjs/cookies-user-id
+     */
+    public function setUserId($userId)
+    {
+        return $this;
+    }
 
-		return $this;
-	}
+    /**
+     * unsets a possible given user id
+     *
+     * @return AnalyticsProviderInterface
+     */
+    public function unsetUserId()
+    {
+        return $this;
+    }
 }
\ No newline at end of file
diff --git a/src/Ipunkt/LaravelAnalytics/TrackingBag.php b/src/Ipunkt/LaravelAnalytics/TrackingBag.php
index eddd4ba..cb5c5d1 100644
--- a/src/Ipunkt/LaravelAnalytics/TrackingBag.php
+++ b/src/Ipunkt/LaravelAnalytics/TrackingBag.php
@@ -1,49 +1,56 @@
-<?php namespace Ipunkt\LaravelAnalytics;
+<?php
+
+namespace Ipunkt\LaravelAnalytics;
 
 use Ipunkt\LaravelAnalytics\Contracts\TrackingBagInterface;
 use Session;
 
+/**
+ * Class TrackingBag
+ *
+ * @package Ipunkt\LaravelAnalytics
+ */
 class TrackingBag implements TrackingBagInterface
 {
-	/**
-	 * session identifier
-	 *
-	 * @var string
-	 */
-	private $sessionIdentifier = 'analytics.tracking';
-
-	/**
-	 * adds a tracking
-	 *
-	 * @param string $tracking
-	 */
-	public function add($tracking)
-	{
-		$sessionTracks = [];
-		if (Session::has($this->sessionIdentifier)) {
-			$sessionTracks = Session::get($this->sessionIdentifier);
-		}
-
-		//	prevent duplicates in session
-		$trackingKey = md5($tracking);
-		$sessionTracks[$trackingKey] = $tracking;
-
-		Session::flash($this->sessionIdentifier, $sessionTracks);
-	}
-
-	/**
-	 * returns all trackings
-	 *
-	 * @return array
-	 */
-	public function get()
-	{
-		$trackings = [];
-		if (Session::has($this->sessionIdentifier)) {
-			$trackings = Session::get($this->sessionIdentifier);
-			Session::forget($this->sessionIdentifier);
-		}
-
-		return $trackings;
-	}
+    /**
+     * session identifier
+     *
+     * @var string
+     */
+    private $sessionIdentifier = 'analytics.tracking';
+
+    /**
+     * adds a tracking
+     *
+     * @param string $tracking
+     */
+    public function add($tracking)
+    {
+        $sessionTracks = [];
+        if (Session::has($this->sessionIdentifier)) {
+            $sessionTracks = Session::get($this->sessionIdentifier);
+        }
+
+        //	prevent duplicates in session
+        $trackingKey = md5($tracking);
+        $sessionTracks[$trackingKey] = $tracking;
+
+        Session::flash($this->sessionIdentifier, $sessionTracks);
+    }
+
+    /**
+     * returns all trackings
+     *
+     * @return array
+     */
+    public function get()
+    {
+        $trackings = [];
+        if (Session::has($this->sessionIdentifier)) {
+            $trackings = Session::get($this->sessionIdentifier);
+            Session::forget($this->sessionIdentifier);
+        }
+
+        return $trackings;
+    }
 }
diff --git a/src/helpers.php b/src/helpers.php
index 01dad9a..e0ba2d1 100644
--- a/src/helpers.php
+++ b/src/helpers.php
@@ -5,6 +5,7 @@
  * taken from Illuminate/Foundation/helpers.php from laravel 5.
  */
 
+use Illuminate\Support\Str;
 
 if (! function_exists('env')) {
     /**