diff --git a/Example/Pods/Pods.xcodeproj/project.pbxproj b/Example/Pods/Pods.xcodeproj/project.pbxproj
index b76648f4..8998dd69 100644
--- a/Example/Pods/Pods.xcodeproj/project.pbxproj
+++ b/Example/Pods/Pods.xcodeproj/project.pbxproj
@@ -991,7 +991,7 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 1100;
-				LastUpgradeCheck = 1100;
+				LastUpgradeCheck = 1030;
 				TargetAttributes = {
 					9AF8AE8821E967844EEF26BBB341564D = {
 						LastSwiftMigration = 1020;
@@ -1327,7 +1327,6 @@
 			baseConfigurationReference = 2C723040DECD495E1AAC81F5AA497C97 /* Pods-macOSDFULibrary_Example.release.xcconfig */;
 			buildSettings = {
 				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = NO;
-				ARCHS = "$(ARCHS_STANDARD_64_BIT)";
 				CLANG_ENABLE_OBJC_WEAK = NO;
 				CODE_SIGN_IDENTITY = "";
 				"CODE_SIGN_IDENTITY[sdk=appletvos*]" = "";
@@ -1362,7 +1361,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 6CCC32CD1F9DE588C70537578CFC9DB9 /* iOSDFULibrary-macOS.xcconfig */;
 			buildSettings = {
-				ARCHS = "$(ARCHS_STANDARD_64_BIT)";
 				CLANG_ENABLE_OBJC_WEAK = NO;
 				CODE_SIGN_IDENTITY = "";
 				"CODE_SIGN_IDENTITY[sdk=appletvos*]" = "";
@@ -1429,7 +1427,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7D90563942E115795A1F5E9E6C7A0D26 /* ZIPFoundation-macOS.xcconfig */;
 			buildSettings = {
-				ARCHS = "$(ARCHS_STANDARD_64_BIT)";
 				CLANG_ENABLE_OBJC_WEAK = NO;
 				CODE_SIGN_IDENTITY = "";
 				"CODE_SIGN_IDENTITY[sdk=appletvos*]" = "";
@@ -1464,7 +1461,6 @@
 			baseConfigurationReference = 890A09B61D0F51EA84B75D5E02FE58D2 /* Pods-macOSDFULibrary_Example.debug.xcconfig */;
 			buildSettings = {
 				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = NO;
-				ARCHS = "$(ARCHS_STANDARD_64_BIT)";
 				CLANG_ENABLE_OBJC_WEAK = NO;
 				CODE_SIGN_IDENTITY = "";
 				"CODE_SIGN_IDENTITY[sdk=appletvos*]" = "";
@@ -1499,7 +1495,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 6CCC32CD1F9DE588C70537578CFC9DB9 /* iOSDFULibrary-macOS.xcconfig */;
 			buildSettings = {
-				ARCHS = "$(ARCHS_STANDARD_64_BIT)";
 				CLANG_ENABLE_OBJC_WEAK = NO;
 				CODE_SIGN_IDENTITY = "";
 				"CODE_SIGN_IDENTITY[sdk=appletvos*]" = "";
@@ -1752,7 +1747,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7D90563942E115795A1F5E9E6C7A0D26 /* ZIPFoundation-macOS.xcconfig */;
 			buildSettings = {
-				ARCHS = "$(ARCHS_STANDARD_64_BIT)";
 				CLANG_ENABLE_OBJC_WEAK = NO;
 				CODE_SIGN_IDENTITY = "";
 				"CODE_SIGN_IDENTITY[sdk=appletvos*]" = "";
diff --git a/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Zip-iOS.xcscheme b/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Zip-iOS.xcscheme
index 351b6d73..5d4533be 100644
--- a/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Zip-iOS.xcscheme
+++ b/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Zip-iOS.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1020"
+   LastUpgradeVersion = "1030"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Zip-macOS.xcscheme b/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Zip-macOS.xcscheme
index b4ef92d6..4fb0a5ea 100644
--- a/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Zip-macOS.xcscheme
+++ b/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Zip-macOS.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1020"
+   LastUpgradeVersion = "1030"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-iOS.xcscheme b/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-iOS.xcscheme
index 20a5279c..88fd1ff7 100644
--- a/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-iOS.xcscheme
+++ b/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-iOS.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1020"
+   LastUpgradeVersion = "1030"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -14,7 +14,7 @@
             buildForAnalyzing = "YES">
             <BuildableReference
                BuildableIdentifier = "primary"
-               BlueprintIdentifier = "6C62C12CF3E12DC4C73C47D64E9A13BA"
+               BlueprintIdentifier = "D5D94E351BD6926C6DC33FBD834E16AC"
                BuildableName = "iOSDFULibrary.framework"
                BlueprintName = "iOSDFULibrary-iOS"
                ReferencedContainer = "container:Pods.xcodeproj">
@@ -45,7 +45,7 @@
       <MacroExpansion>
          <BuildableReference
             BuildableIdentifier = "primary"
-            BlueprintIdentifier = "6C62C12CF3E12DC4C73C47D64E9A13BA"
+            BlueprintIdentifier = "D5D94E351BD6926C6DC33FBD834E16AC"
             BuildableName = "iOSDFULibrary.framework"
             BlueprintName = "iOSDFULibrary-iOS"
             ReferencedContainer = "container:Pods.xcodeproj">
diff --git a/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-macOS.xcscheme b/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-macOS.xcscheme
index abdba8e5..add170f5 100644
--- a/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-macOS.xcscheme
+++ b/Example/Pods/Pods.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-macOS.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1020"
+   LastUpgradeVersion = "1030"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -14,7 +14,7 @@
             buildForAnalyzing = "YES">
             <BuildableReference
                BuildableIdentifier = "primary"
-               BlueprintIdentifier = "B80353FE3CEF70529DB8DB81E67C1C39"
+               BlueprintIdentifier = "79F9638EA00F4594D84B597FE45CD2DC"
                BuildableName = "iOSDFULibrary.framework"
                BlueprintName = "iOSDFULibrary-macOS"
                ReferencedContainer = "container:Pods.xcodeproj">
@@ -45,7 +45,7 @@
       <MacroExpansion>
          <BuildableReference
             BuildableIdentifier = "primary"
-            BlueprintIdentifier = "B80353FE3CEF70529DB8DB81E67C1C39"
+            BlueprintIdentifier = "79F9638EA00F4594D84B597FE45CD2DC"
             BuildableName = "iOSDFULibrary.framework"
             BlueprintName = "iOSDFULibrary-macOS"
             ReferencedContainer = "container:Pods.xcodeproj">
diff --git a/Example/Pods/Target Support Files/iOSDFULibrary-iOS/iOSDFULibrary-iOS-Info.plist b/Example/Pods/Target Support Files/iOSDFULibrary-iOS/iOSDFULibrary-iOS-Info.plist
index 7be5c8c8..f4569cc5 100644
--- a/Example/Pods/Target Support Files/iOSDFULibrary-iOS/iOSDFULibrary-iOS-Info.plist	
+++ b/Example/Pods/Target Support Files/iOSDFULibrary-iOS/iOSDFULibrary-iOS-Info.plist	
@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>4.5.0</string>
+	<string>4.5.1</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
diff --git a/Example/Pods/Target Support Files/iOSDFULibrary-macOS/iOSDFULibrary-macOS-Info.plist b/Example/Pods/Target Support Files/iOSDFULibrary-macOS/iOSDFULibrary-macOS-Info.plist
index 7be5c8c8..f4569cc5 100644
--- a/Example/Pods/Target Support Files/iOSDFULibrary-macOS/iOSDFULibrary-macOS-Info.plist	
+++ b/Example/Pods/Target Support Files/iOSDFULibrary-macOS/iOSDFULibrary-macOS-Info.plist	
@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>4.5.0</string>
+	<string>4.5.1</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
diff --git a/Example/iOSDFULibrary.xcodeproj/project.pbxproj b/Example/iOSDFULibrary.xcodeproj/project.pbxproj
index cafc4d3c..60dad698 100644
--- a/Example/iOSDFULibrary.xcodeproj/project.pbxproj
+++ b/Example/iOSDFULibrary.xcodeproj/project.pbxproj
@@ -20,6 +20,8 @@
 		52237250202B117700068EE4 /* CustomTestSet.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5223724F202B117700068EE4 /* CustomTestSet.swift */; };
 		5223729B202B275F00068EE4 /* Firmwares in Resources */ = {isa = PBXBuildFile; fileRef = 5223729A202B275F00068EE4 /* Firmwares */; };
 		5223729D2036DDFC00068EE4 /* nRF52840TestSet.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5223729C2036DDFC00068EE4 /* nRF52840TestSet.swift */; };
+		52A9C167230D633A0036792A /* changelog.md in Resources */ = {isa = PBXBuildFile; fileRef = 52A9C166230D633A0036792A /* changelog.md */; };
+		52A9C169230D63410036792A /* documentation.md in Resources */ = {isa = PBXBuildFile; fileRef = 52A9C168230D63410036792A /* documentation.md */; };
 		52F6AD6222B2429300F0D7DF /* TestFirmwares in Resources */ = {isa = PBXBuildFile; fileRef = 52F6AD6122B2429300F0D7DF /* TestFirmwares */; };
 		52FB0B022220168D00B1E575 /* PeripheralCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = 52FB0B012220168D00B1E575 /* PeripheralCell.swift */; };
 		52FB0B04222019C700B1E575 /* MainNavigationViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 52FB0B03222019C700B1E575 /* MainNavigationViewController.swift */; };
@@ -62,6 +64,8 @@
 		5223724F202B117700068EE4 /* CustomTestSet.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CustomTestSet.swift; sourceTree = "<group>"; };
 		5223729A202B275F00068EE4 /* Firmwares */ = {isa = PBXFileReference; lastKnownFileType = folder; path = Firmwares; sourceTree = "<group>"; };
 		5223729C2036DDFC00068EE4 /* nRF52840TestSet.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = nRF52840TestSet.swift; sourceTree = "<group>"; };
+		52A9C166230D633A0036792A /* changelog.md */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = net.daringfireball.markdown; name = changelog.md; path = ../changelog.md; sourceTree = "<group>"; };
+		52A9C168230D63410036792A /* documentation.md */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = net.daringfireball.markdown; name = documentation.md; path = ../documentation.md; sourceTree = "<group>"; };
 		52F6AD6122B2429300F0D7DF /* TestFirmwares */ = {isa = PBXFileReference; lastKnownFileType = folder; path = TestFirmwares; sourceTree = "<group>"; };
 		52FB0B012220168D00B1E575 /* PeripheralCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PeripheralCell.swift; sourceTree = "<group>"; };
 		52FB0B03222019C700B1E575 /* MainNavigationViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MainNavigationViewController.swift; sourceTree = "<group>"; };
@@ -229,6 +233,8 @@
 			children = (
 				3B0557890E61EFF388A8734B /* iOSDFULibrary.podspec */,
 				8EE39CA79039E8FFBDA0C9D3 /* README.md */,
+				52A9C166230D633A0036792A /* changelog.md */,
+				52A9C168230D63410036792A /* documentation.md */,
 				DAEFE092DC94AFC6C8316559 /* LICENSE */,
 			);
 			name = "Podspec Metadata";
@@ -389,8 +395,10 @@
 			buildActionMask = 2147483647;
 			files = (
 				52F6AD6222B2429300F0D7DF /* TestFirmwares in Resources */,
+				52A9C169230D63410036792A /* documentation.md in Resources */,
 				607FACDB1AFB9204008FA782 /* Main.storyboard in Resources */,
 				52FB0B0622201A4A00B1E575 /* LaunchScreen.storyboard in Resources */,
+				52A9C167230D633A0036792A /* changelog.md in Resources */,
 				5223729B202B275F00068EE4 /* Firmwares in Resources */,
 				607FACDD1AFB9204008FA782 /* Images.xcassets in Resources */,
 			);
diff --git a/Example/iOSDFULibrary.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-Example.xcscheme b/Example/iOSDFULibrary.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-Example.xcscheme
index 7d3d8b6c..bf7ebfee 100644
--- a/Example/iOSDFULibrary.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-Example.xcscheme
+++ b/Example/iOSDFULibrary.xcodeproj/xcshareddata/xcschemes/iOSDFULibrary-Example.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1020"
+   LastUpgradeVersion = "1030"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/LICENSE b/LICENSE
index 34545536..ad026f84 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 BSD 3-Clause License
 
-Copyright (c) 2016, Nordic Semiconductor
+Copyright (c) 2019, Nordic Semiconductor
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
diff --git a/changelog.md b/changelog.md
index 5af69ee2..ce026a68 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,4 +1,7 @@
 ### Changelog
+- **4.5.1**
+    - Bugfix: Fixed an issue where DFU could not be started on iOS 13 (#322). 
+    
 - **4.5.0**
     - Improvement: Hex2Bin converter rewritten to Swift 5.
     - Library released in Swift Package Manager (SPM).
diff --git a/iOSDFULibrary.podspec b/iOSDFULibrary.podspec
index 73dd1638..078a166e 100644
--- a/iOSDFULibrary.podspec
+++ b/iOSDFULibrary.podspec
@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = "iOSDFULibrary"
-  s.version          = "4.5.0"
+  s.version          = "4.5.1"
   s.summary          = "This repository contains a tested library for iOS 9+ devices to perform Device Firmware Update on the nRF5x devices"
   s.description      = <<-DESC
 The nRF5x Series chips are flash-based SoCs, and as such they represent the most flexible solution available. A key feature of the nRF5x Series and their associated software architecture and S-Series SoftDevices is the possibility for Over-The-Air Device Firmware Upgrade (OTA-DFU). See Figure 1. OTA-DFU allows firmware upgrades to be issued and downloaded to products in the field via the cloud and so enables OEMs to fix bugs and introduce new features to products that are already out on the market. This brings added security and flexibility to product development when using the nRF5x Series SoCs.
diff --git a/iOSDFULibrary/Classes/Implementation/DFUServiceInitiator.swift b/iOSDFULibrary/Classes/Implementation/DFUServiceInitiator.swift
index 14655736..56f1db8c 100644
--- a/iOSDFULibrary/Classes/Implementation/DFUServiceInitiator.swift
+++ b/iOSDFULibrary/Classes/Implementation/DFUServiceInitiator.swift
@@ -31,9 +31,9 @@ import CoreBluetooth
     
     //MARK: - Internal variables
     
-    internal let centralManager : CBCentralManager
-    internal var target         : CBPeripheral!
-    internal var file           : DFUFirmware?
+    internal let centralManager   : CBCentralManager
+    internal var targetIdentifier : UUID!
+    internal var file             : DFUFirmware?
     
     internal var queue                 : DispatchQueue
     internal var delegateQueue         : DispatchQueue
@@ -244,7 +244,7 @@ import CoreBluetooth
         self.centralManager = centralManager
         // Just to be sure that manager is not scanning
         self.centralManager.stopScan()
-        self.target = target
+        self.targetIdentifier = target.identifier
         // Default peripheral selector will choose the service UUID as a filter
         self.peripheralSelector = DFUPeripheralSelector()
         // Default UUID helper with standard set of UUIDs
@@ -329,7 +329,7 @@ import CoreBluetooth
         }
         
         // Make sure the target was set by the deprecated init.
-        guard let _ = target else {
+        guard let _ = targetIdentifier else {
             delegate?.dfuError(.failedToConnect, didOccurWithMessage: "Target not specified: use start(target) instead")
             return nil
         }
@@ -394,18 +394,12 @@ import CoreBluetooth
      */
     @objc public func start(targetWithIdentifier uuid: UUID) -> DFUServiceController? {
         // The firmware file must be specified before calling `start(...)`.
-        if file == nil {
+        guard let _ = file else {
             delegate?.dfuError(.fileNotSpecified, didOccurWithMessage: "Firmware not specified")
             return nil
         }
         
-        // As the given peripheral was obtained using a different central manager,
-        // its new instance must be obtained from the new manager.
-        guard let peripheral = self.centralManager.retrievePeripherals(withIdentifiers: [uuid]).first else {
-            delegate?.dfuError(.bluetoothDisabled, didOccurWithMessage: "Could not obtain peripheral instance")
-            return nil
-        }
-        target = peripheral
+        targetIdentifier = uuid
         
         let controller = DFUServiceController()
         let selector   = DFUServiceSelector(initiator: self, controller: controller)
diff --git a/iOSDFULibrary/Classes/Implementation/GenericDFU/DFUPeripheral.swift b/iOSDFULibrary/Classes/Implementation/GenericDFU/DFUPeripheral.swift
index 907af030..061ec5d5 100644
--- a/iOSDFULibrary/Classes/Implementation/GenericDFU/DFUPeripheral.swift
+++ b/iOSDFULibrary/Classes/Implementation/GenericDFU/DFUPeripheral.swift
@@ -50,6 +50,7 @@ internal protocol BaseDFUPeripheralAPI : class, DFUController {
 internal class BaseDFUPeripheral<TD : BasePeripheralDelegate> : NSObject, BaseDFUPeripheralAPI, CBPeripheralDelegate, CBCentralManagerDelegate {
     /// Bluetooth Central Manager used to scan for the peripheral.
     internal let centralManager: CBCentralManager
+    internal let targetIdentifier: UUID
     internal let queue: DispatchQueue
     /// The DFU Target peripheral.
     internal var peripheral: CBPeripheral?
@@ -89,14 +90,13 @@ internal class BaseDFUPeripheral<TD : BasePeripheralDelegate> : NSObject, BaseDF
     
     init(_ initiator: DFUServiceInitiator, _ logger: LoggerHelper) {
         self.centralManager = initiator.centralManager
+        self.targetIdentifier = initiator.targetIdentifier
         self.queue = initiator.queue
         self.logger = logger
         self.experimentalButtonlessServiceInSecureDfuEnabled = initiator.enableUnsafeExperimentalButtonlessServiceInSecureDfu
         self.uuidHelper = initiator.uuidHelper
 
         super.init()
-        // Set the initial peripheral. It may be changed later (flashing App fw after first flashing SD/BL)
-        self.peripheral = initiator.target
     }
     
     // MARK: - Base DFU Peripheral API
@@ -109,14 +109,20 @@ internal class BaseDFUPeripheral<TD : BasePeripheralDelegate> : NSObject, BaseDF
             // Central manager not ready. Wait for poweredOn state.
             return
         }
+        // Set the initial peripheral. It may be changed later (flashing App fw after first flashing SD/BL).
+        guard let peripheral = centralManager.retrievePeripherals(withIdentifiers: [targetIdentifier]).first else {
+            delegate?.error(.bluetoothDisabled, didOccurWithMessage: "Could not obtain peripheral instance")
+            return
+        }
+        self.peripheral = peripheral
         
-        if peripheral!.state != .connected {
+        if peripheral.state != .connected {
             connect()
         } else {
-            let name = peripheral!.name ?? "Unknown device"
+            let name = peripheral.name ?? "Unknown device"
             logger.i("Connected to \(name)")
             
-            let dfuService = findDfuService(in: peripheral!.services)
+            let dfuService = findDfuService(in: peripheral.services)
             if dfuService == nil {
                 // DFU service has not been found, but it doesn't matter it's not there.
                 // Perhaps the user's application didn't discover it. Let's discover DFU services.