diff --git a/.env.example b/.env.example
index 06c04d4..b250edc 100644
--- a/.env.example
+++ b/.env.example
@@ -1,21 +1,20 @@
 #### PRODUCTION
-# VITE_IFRAME_URL=https://iframe.string-api.xyz
-# VITE_API_URL=https://api.string-api.xyz
+PROD_IFRAME_URL=https://iframe.string-api.xyz
+PROD_API_URL=https://api.string-api.xyz
 
 #### DEVELOPMENT
-# VITE_IFRAME_URL=https://iframe-app.dev.string-api.xyz
-# VITE_API_URL=https://string-api.dev.string-api.xyz
+DEV_IFRAME_URL=https://iframe-app.dev.string-api.xyz
+DEV_API_URL=https://string-api.dev.string-api.xyz
 
 #### SANDBOX
-# VITE_IFRAME_URL=https://iframe-app.dev.string-api.xyz
-# VITE_API_URL=https://api.sandbox.string-api.xyz
+SBOX_IFRAME_URL=https://iframe-app.dev.string-api.xyz
+SBOX_API_URL=https://api.sandbox.string-api.xyz
 
 #### LOCAL
-VITE_IFRAME_URL=http://localhost:4040
-VITE_API_URL=http://localhost:5555
+LOCAL_IFRAME_URL=http://localhost:4040
+LOCAL_API_URL=http://localhost:5555
 
-VITE_STRING_API_KEY=str...
-
-#### ANALYTICS
 VITE_ANALYTICS_LIB_PK=
-VITE_ANALYTICS_SUBDOMAIN_URL=https://metrics.string.xyz
\ No newline at end of file
+VITE_ANALYTICS_SUBDOMAIN_URL=https://metrics.string.xyz
+
+VITE_STRING_API_KEY=str...
diff --git a/rollup.config.js b/rollup.config.js
index 6944650..4fc40b2 100644
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -11,8 +11,29 @@ config();
 
 const version = process.env.npm_package_version
 
-if (!process.env.VITE_IFRAME_URL || !process.env.VITE_API_URL || !process.env.VITE_ANALYTICS_LIB_PK) {
-	throw Error("Missing variables in .env")
+const ENV_TABLE = [
+	{ name: 'PROD_IFRAME_URL', value: process.env.PROD_IFRAME_URL },
+	{ name: 'PROD_API_URL', value: process.env.PROD_API_URL },
+	{ name: 'SBOX_IFRAME_URL', value: process.env.SBOX_IFRAME_URL },
+	{ name: 'SBOX_API_URL', value: process.env.SBOX_API_URL },
+	{ name: 'DEV_IFRAME_URL', value: process.env.DEV_IFRAME_URL },
+	{ name: 'DEV_API_URL', value: process.env.DEV_API_URL },
+	{ name: 'LOCAL_IFRAME_URL', value: process.env.LOCAL_IFRAME_URL },
+	{ name: 'LOCAL_API_URL', value: process.env.LOCAL_API_URL },
+]
+
+for (const env of ENV_TABLE) {
+	if (!env.value) {
+		throw Error(`Missing ${env.name} in .env`)
+	}
+}
+
+if (!process.env.VITE_ANALYTICS_LIB_PK) {
+	throw Error(`Missing VITE_ANALYTICS_LIB_PK in .env`)
+}
+
+if (!process.env.VITE_ANALYTICS_SUBDOMAIN_URL) {
+	throw Error(`Missing VITE_ANALYTICS_SUBDOMAIN_URL in .env`)
 }
 
 export default {
@@ -30,9 +51,12 @@ export default {
 		resolve({ jsnext: true, preferBuiltins: true, browser: true }),
 		replace({
 			values: {
-				'import.meta.env.VITE_IFRAME_URL': JSON.stringify(new URL(process.env.VITE_IFRAME_URL).origin),
-				'import.meta.env.VITE_API_URL': JSON.stringify(new URL(process.env.VITE_API_URL).origin),
+				...ENV_TABLE.reduce((acc, env) => {
+					acc[`import.meta.env.${env.name}`] = JSON.stringify(new URL(env.value).origin);
+					return acc
+				}, {}),
 				'import.meta.env.VITE_ANALYTICS_LIB_PK': JSON.stringify(process.env.VITE_ANALYTICS_LIB_PK),
+				'import.meta.env.VITE_ANALYTICS_SUBDOMAIN_URL': JSON.stringify(process.env.VITE_ANALYTICS_SUBDOMAIN_URL),
 			},
 			preventAssignment: true
 		}),
diff --git a/src/lib/StringPay.d.ts b/src/lib/StringPay.d.ts
index c615dab..3bd9086 100644
--- a/src/lib/StringPay.d.ts
+++ b/src/lib/StringPay.d.ts
@@ -1,6 +1,4 @@
 export interface StringPayload {
-    options?: StringOptions;
-    apiKey: string;
     name: string;
     collection?: string;
     currency: string;
@@ -17,16 +15,21 @@ export interface StringPayload {
     gasLimit?: string;
 }
 
+export type StringSDKEnvironment = "PROD" | "SANDBOX" | "DEV" | "LOCAL";
+
 export interface StringOptions {
+    env: StringSDKEnvironment;
+    publicKey: string;
     bypassDeviceCheck?: boolean;
 }
 
 export declare class StringPay {
-	container?: Element;
-	frame?: HTMLIFrameElement;
-	payload?: StringPayload;
 	isLoaded: boolean;
+	payload?: StringPayload;
+	frame?: HTMLIFrameElement;
+	container?: Element;
 	onFrameLoad: () => void;
 	onFrameClose: () => void;
+	init(options: StringOptions): void;
 	loadFrame(payload: StringPayload): void;
 }
diff --git a/src/lib/StringPay.ts b/src/lib/StringPay.ts
index 20fc3f0..5f786ba 100644
--- a/src/lib/StringPay.ts
+++ b/src/lib/StringPay.ts
@@ -1,8 +1,6 @@
 import { createServices, type Services } from "./services";
 
 export interface StringPayload {
-    options?: StringOptions
-    apiKey: string;
     name: string;
     collection?: string;
     currency: string;
@@ -19,32 +17,71 @@ export interface StringPayload {
     gasLimit?: string;
 }
 
+export type StringSDKEnvironment = "PROD" | "SANDBOX" | "DEV" | "LOCAL";
+
 export interface StringOptions {
+    env: StringSDKEnvironment;
+    publicKey: string;
     bypassDeviceCheck?: boolean;
 }
 
-const IFRAME_URL = import.meta.env.VITE_IFRAME_URL;
-const API_URL = import.meta.env.VITE_API_URL;
+type StringEnvDetails = {
+    IFRAME_URL: string;
+    API_URL: string;
+}
+
+const ENV_TABLE: Record<StringSDKEnvironment, StringEnvDetails> = {
+    "PROD": {
+        IFRAME_URL: import.meta.env.PROD_IFRAME_URL,
+        API_URL: import.meta.env.PROD_API_URL,
+    },
+    "SANDBOX": {
+        IFRAME_URL: import.meta.env.SBOX_IFRAME_URL,
+        API_URL: import.meta.env.SBOX_API_URL,
+    },
+    "DEV": {
+        IFRAME_URL: import.meta.env.DEV_IFRAME_URL,
+        API_URL: import.meta.env.DEV_API_URL,
+    },
+    "LOCAL": {
+        IFRAME_URL: import.meta.env.LOCAL_IFRAME_URL,
+        API_URL: import.meta.env.LOCAL_API_URL,
+    }
+}
 
 const err = (msg: string) => {
     console.error("[String Pay] " + msg);
 };
 
 export class StringPay {
-    container?: Element;
-    frame?: HTMLIFrameElement;
-    payload?: StringPayload;
     isLoaded = false;
-    services: Services;
-    private _loadIframeCallback = () => {};
-
-    constructor(loadIframeCallback: () => void) {
-        this._loadIframeCallback = loadIframeCallback;
-    }
+    payload?: StringPayload;
+    frame?: HTMLIFrameElement;
+    container?: Element;
+    #services: Services;
+    private _IFRAME_URL: string;
 
     onFrameLoad = () => {};
     onFrameClose = () => {};
 
+    init(options: StringOptions) {
+        const envDetails = ENV_TABLE[options.env];
+        if (!envDetails) {
+            return err(`Invalid environment: ${options.env}`);
+        }
+
+        if (!options.publicKey) return err("You need an API key to use the String SDK");
+        if (options.publicKey.slice(0, 4) !== "str.") return err(`Invalid API Key: ${options.publicKey}`);
+
+        this._IFRAME_URL = envDetails.IFRAME_URL;
+        this.#services = createServices({
+            baseUrl: envDetails.API_URL,
+            iframeUrl: envDetails.IFRAME_URL,
+            apiKey: options.publicKey,
+            bypassDeviceCheck: options.bypassDeviceCheck ?? false
+        });
+    }
+
     async loadFrame(payload: StringPayload) {
         // make sure there is a wallet connected
         if (!window.ethereum || !window.ethereum.selectedAddress) return err("No wallet connected, please connect wallet");
@@ -59,10 +96,9 @@ export class StringPay {
 
         // Validate payload
         if (!payload) return err("No payload specified");
-        if (!payload.apiKey) return err("You must have an api key in your payload");
-        if (payload.apiKey.slice(0, 4) !== "str.") return err(`Invalid API Key: ${payload.apiKey}`);
         if (!payload.userAddress) return err("No user address found, please connect wallet");
-        if (!IFRAME_URL) return err("IFRAME_URL not specified");
+        if (!this._IFRAME_URL) return err("IFRAME_URL not specified. Did you call init()?");
+        if (!this.#services) return err("Services not initialized. Did you call init()?");
 
         // Set payload
         this.payload = payload;
@@ -72,7 +108,8 @@ export class StringPay {
         iframe.style.width = "100vh";
         iframe.style.height = "700px";
         iframe.style.overflow = "none";
-        iframe.src = IFRAME_URL;
+        iframe.src = this._IFRAME_URL;
+
         container.appendChild(iframe);
         this.container = container;
         this.frame = iframe;
@@ -80,26 +117,15 @@ export class StringPay {
         // set the default gas limit
         this.payload.gasLimit = "8000000"; // TODO: Do we want this value to change dynamically?
 
-        this._loadIframeCallback();
+        this.#services.eventsService.unregisterEvents();
+        this.#services.eventsService.registerEvents();
     }
 }
 
 function main() {
-    // This is the starting point of the library
-    // We create services that contain all the logic for the library
-    // StringPay is the main class that is exported to the user
-    // We also create a callback that is called when the iframe is loaded. This is used to register events
-
-    const services = createServices({
-        apiUrl: API_URL,
-    });
-
-    const loadIframeCallback = () => {
-        services.eventsService.unregisterEvents();
-        services.eventsService.registerEvents();
-    };
+    // Expose the StringPay instance to the window
 
-    const stringPay = new StringPay(loadIframeCallback);
+    const stringPay = new StringPay();
     (<any>window).StringPay = stringPay;
 }
 
diff --git a/src/lib/services/apiClient.service.ts b/src/lib/services/apiClient.service.ts
index 0d02e16..b5bc2a5 100644
--- a/src/lib/services/apiClient.service.ts
+++ b/src/lib/services/apiClient.service.ts
@@ -2,9 +2,8 @@ import axios from "redaxios";
 
 // TODO: Fix timeout issue
 
-export function createApiClient({ baseUrl }: ApiClientOptions): ApiClient {
+export function createApiClient({ baseUrl, apiKey }: ApiClientOptions): ApiClient {
     let _userWalletAddress = "";
-    let apiKey = "";
 
     const commonHeaders: any = {
         "Content-Type": "application/json",
@@ -18,7 +17,6 @@ export function createApiClient({ baseUrl }: ApiClientOptions): ApiClient {
     });
 
     const setWalletAddress = (addr: string) => (_userWalletAddress = addr);
-    const setApiKey = (key: string) => (apiKey = key);
 
     async function createApiKey() {
         const { data } = await httpClient.post<{ apiKey: string }>("/apikeys");
@@ -230,8 +228,7 @@ export function createApiClient({ baseUrl }: ApiClientOptions): ApiClient {
         getUserStatus,
         getQuote,
         transact,
-        setWalletAddress,
-        setApiKey,
+        setWalletAddress
     };
 }
 
@@ -250,7 +247,6 @@ export interface ApiClient {
     getQuote: (payload: QuoteRequestPayload) => Promise<TransactPayload>;
     transact: (quote: TransactPayload) => Promise<TransactionResponse>;
     setWalletAddress: (walletAddress: string) => void;
-    setApiKey: (apiKey: string) => void;
 }
 
 interface ApiKeyResponse {
@@ -339,4 +335,5 @@ export interface QuoteRequestPayload {
 
 export interface ApiClientOptions {
     baseUrl: string;
+    apiKey: string;
 }
diff --git a/src/lib/services/auth.service.ts b/src/lib/services/auth.service.ts
index 169a007..a6cad1d 100644
--- a/src/lib/services/auth.service.ts
+++ b/src/lib/services/auth.service.ts
@@ -1,17 +1,11 @@
 import type { ApiClient, User } from './apiClient.service';
 import type { LocationService, VisitorData } from './location.service';
 
-export function createAuthService({ apiClient, locationService }: { apiClient: ApiClient, locationService: LocationService }): AuthService {
+export function createAuthService({ apiClient, locationService, bypassDeviceCheck }: AuthServiceParams): AuthService {
 	const previousAttempt = { signature: "", nonce: "" };
 
-	let _bypassDeviceCheck = false;
-
-	const setBypassDeviceCheck = (value?: boolean) => {
-		_bypassDeviceCheck = value || false;
-	};
-	
 	const login = async (nonce: string, signature: string, visitorData?: VisitorData) => {
-		const data = await apiClient.loginUser(nonce, signature, visitorData, _bypassDeviceCheck);
+		const data = await apiClient.loginUser(nonce, signature, visitorData, bypassDeviceCheck);
 		return data;
 	};
 
@@ -85,15 +79,19 @@ export function createAuthService({ apiClient, locationService }: { apiClient: A
 		loginOrCreateUser,
 		fetchLoggedInUser,
 		retryLogin,
-		logout,
-		setBypassDeviceCheck
+		logout
 	};
 }
 
+export interface AuthServiceParams {
+	apiClient: ApiClient;
+	locationService: LocationService;
+	bypassDeviceCheck: boolean;
+}
+
 export interface AuthService {
 	loginOrCreateUser: (walletAddress: string) => Promise<{ user: User }>;
 	fetchLoggedInUser: (walletAddress: string) => Promise<User | null>;
 	retryLogin: () => Promise<{ user: User }>;
 	logout: () => Promise<any>;
-	setBypassDeviceCheck: (value?: boolean) => void;
 }
\ No newline at end of file
diff --git a/src/lib/services/events.service.ts b/src/lib/services/events.service.ts
index adfbb14..c1892e0 100644
--- a/src/lib/services/events.service.ts
+++ b/src/lib/services/events.service.ts
@@ -5,7 +5,6 @@ import type { LocationService } from "./location.service";
 import type { QuoteService } from "./quote.service";
 
 const CHANNEL = "STRING_PAY";
-const IFRAME_URL = new URL(import.meta.env.VITE_IFRAME_URL).origin;
 
 export enum Events {
     LOAD_PAYLOAD = "load_payload",
@@ -29,47 +28,7 @@ export enum Events {
 
 const eventHandlers: Record<string, (event: StringEvent, stringPay: StringPay) => void> = {};
 
-const _handleEvent = async (e: any) => {
-    if (e.origin !== IFRAME_URL) return;
-
-    const stringPay: StringPay = (<any>window).StringPay;
-
-    try {
-        const payload = JSON.parse(e.data);
-        const channel = payload.channel;
-        const event = <StringEvent>payload.event;
-        if (channel === CHANNEL) {
-            const handler = eventHandlers[event.eventName];
-            if (handler) await handler(event, stringPay);
-            else console.debug("SDK :: Unhandled event: ", event);
-        }
-    } catch (error) {
-        console.error("sdk: _handleEvent error: ", error);
-    }
-};
-
-const registerEvents = () => {
-    unregisterEvents();
-
-    window.addEventListener("message", _handleEvent);
-};
-
-const unregisterEvents = () => {
-    window.removeEventListener("message", _handleEvent);
-};
-
-function cleanup() {
-    unregisterEvents();
-
-    if ((<any>window).StringPay) {
-        (<any>window).StringPay.frame?.remove();
-        (<any>window).StringPay.frame = undefined;
-        (<any>window).StringPay.isLoaded = false;
-        (<any>window).StringPay.onFrameClose();
-    }
-}
-
-export function createEventsService(authService: AuthService, quoteService: QuoteService, apiClient: ApiClient, locationService: LocationService) {
+export function createEventsService(iframeUrl: string, authService: AuthService, quoteService: QuoteService, apiClient: ApiClient, locationService: LocationService) {
     const sendEvent = <T = any>(frame: HTMLIFrameElement, eventName: string, data?: T, error?: any) => {
         if (!frame) {
             err("a frame was not provided to sendEvent");
@@ -84,6 +43,46 @@ export function createEventsService(authService: AuthService, quoteService: Quot
         frame.contentWindow?.postMessage(message, "*");
     };
 
+    const _handleEvent = async (e: any) => {
+        if (e.origin !== iframeUrl) return;
+    
+        const stringPay: StringPay = (<any>window).StringPay;
+    
+        try {
+            const payload = JSON.parse(e.data);
+            const channel = payload.channel;
+            const event = <StringEvent>payload.event;
+            if (channel === CHANNEL) {
+                const handler = eventHandlers[event.eventName];
+                if (handler) await handler(event, stringPay);
+                else console.debug("SDK :: Unhandled event: ", event);
+            }
+        } catch (error) {
+            console.error("sdk: _handleEvent error: ", error);
+        }
+    };
+
+    const registerEvents = () => {
+        unregisterEvents();
+    
+        window.addEventListener("message", _handleEvent);
+    };
+    
+    const unregisterEvents = () => {
+        window.removeEventListener("message", _handleEvent);
+    };
+
+    function cleanup() {
+        unregisterEvents();
+    
+        if ((<any>window).StringPay) {
+            (<any>window).StringPay.frame?.remove();
+            (<any>window).StringPay.frame = undefined;
+            (<any>window).StringPay.isLoaded = false;
+            (<any>window).StringPay.onFrameClose();
+        }
+    }
+
     //
     eventHandlers[Events.IFRAME_READY] = onIframeReady;
     eventHandlers[Events.IFRAME_CLOSE] = onIframeClose;
@@ -104,8 +103,6 @@ export function createEventsService(authService: AuthService, quoteService: Quot
         if (!stringPay.frame || !stringPay.payload) throw new Error("Iframe not ready");
 
         apiClient.setWalletAddress(stringPay.payload.userAddress);
-        apiClient.setApiKey(stringPay.payload.apiKey);
-        authService.setBypassDeviceCheck(stringPay.payload.options?.bypassDeviceCheck);
 
         // init fp service
         locationService.getFPInstance().catch((err) => console.debug("getFPInstance error: ", err));
diff --git a/src/lib/services/index.ts b/src/lib/services/index.ts
index a81e215..092f468 100644
--- a/src/lib/services/index.ts
+++ b/src/lib/services/index.ts
@@ -4,20 +4,13 @@ import { createAuthService } from "./auth.service";
 import { createQuoteService } from "./quote.service";
 import { createEventsService } from "./events.service";
 
-export interface Services {
-    apiClient: ReturnType<typeof createApiClient>;
-    locationService: ReturnType<typeof createLocationService>;
-    authService: ReturnType<typeof createAuthService>;
-    quoteService: ReturnType<typeof createQuoteService>;
-}
-
-export function createServices({ apiUrl }: { apiUrl: string }): Services {
-    const apiClient = createApiClient({ baseUrl: apiUrl });
+export function createServices({ baseUrl, iframeUrl, apiKey, bypassDeviceCheck = false }: ServiceParams): Services {
+    const apiClient = createApiClient({ baseUrl, apiKey });
 
     const locationService = createLocationService();
-    const authService = createAuthService({ apiClient, locationService });
+    const authService = createAuthService({ apiClient, locationService, bypassDeviceCheck });
     const quoteService = createQuoteService(apiClient);
-    const eventsService = createEventsService(authService, quoteService, apiClient, locationService);
+    const eventsService = createEventsService(iframeUrl, authService, quoteService, apiClient, locationService);
 
     return {
         apiClient,
@@ -28,6 +21,13 @@ export function createServices({ apiUrl }: { apiUrl: string }): Services {
     };
 }
 
+export interface ServiceParams {
+    baseUrl: string;
+    iframeUrl: string;
+    apiKey: string;
+    bypassDeviceCheck?: boolean;
+}
+
 // services interface
 export interface Services {
     apiClient: ReturnType<typeof createApiClient>;
diff --git a/src/lib/services/location.service.ts b/src/lib/services/location.service.ts
index 77b783e..434e9b8 100644
--- a/src/lib/services/location.service.ts
+++ b/src/lib/services/location.service.ts
@@ -1,6 +1,6 @@
 import * as FingerprintJS from '@fingerprintjs/fingerprintjs-pro';
 
-const CUSTOM_SUBDOMAIN = "https://metrics.string.xyz";
+const CUSTOM_SUBDOMAIN = import.meta.env.VITE_ANALYTICS_SUBDOMAIN_URL || "";
 const apiKey = import.meta.env.VITE_ANALYTICS_LIB_PK || "";
 
 export function createLocationService(options = {}): LocationService {
diff --git a/src/routes/+page.svelte b/src/routes/+page.svelte
index e05b42b..1cd77b3 100644
--- a/src/routes/+page.svelte
+++ b/src/routes/+page.svelte
@@ -9,7 +9,6 @@
 	const signerAddress = writable("");
 
 	$: payload = {
-		apiKey,
 		name: "String Demo NFT",
 		collection: "String Demo",
 		imageSrc:
@@ -29,6 +28,16 @@
 	$: disabled = !$signerAddress;
 
 	onMount(async () => {
+		if (!window.StringPay) {
+			console.error("[String Pay] Cannot find stringpay module in DOM");
+		}
+
+		window.StringPay.init({
+			env: "LOCAL",
+			publicKey: apiKey
+		});
+
+
 		const accounts = await window.ethereum.request({
 			method: "eth_requestAccounts",
 		});
diff --git a/src/test/Events.spec.ts b/src/test/Events.spec.ts
index 8af54a2..d85023e 100644
--- a/src/test/Events.spec.ts
+++ b/src/test/Events.spec.ts
@@ -4,7 +4,7 @@ import { Events } from "$lib/services/events.service";
 
 describe.skip("Events.ts", () => {
     beforeEach(() => {
-        (<any>window).StringPay = new StringPay(() => {});
+        (<any>window).StringPay = new StringPay();
 
         window.StringPay.frame = document.createElement("iframe");
         window.StringPay.payload = testPayload;
diff --git a/src/test/StringPayButton.spec.ts b/src/test/StringPayButton.spec.ts
index 19787d6..7348382 100644
--- a/src/test/StringPayButton.spec.ts
+++ b/src/test/StringPayButton.spec.ts
@@ -15,7 +15,7 @@ describe("StringPayButton.svelte", () => {
         container.classList.add("string-pay-frame");
         document.body.appendChild(container);
 
-        (<any>window).StringPay = new StringPay(() => {});
+        (<any>window).StringPay = new StringPay();
 
         render(StringPayButton, { payload: testPayload });
         const button = screen.getByRole("button");
diff --git a/src/test/mock.ts b/src/test/mock.ts
index 18c0d1a..9882beb 100644
--- a/src/test/mock.ts
+++ b/src/test/mock.ts
@@ -1,10 +1,8 @@
 import type { StringPayload } from '../lib/StringPay';
 
-const apiKey = import.meta.env.VITE_STRING_API_KEY
 const userAddr = "0x000000"
 
 export const testPayload: StringPayload = {
-	apiKey,
 	name: "String Demo NFT",
 	collection: "String Demo",
 	imageSrc: "https://gateway.pinata.cloud/ipfs/bafybeibtmy26mac47n5pp6srds76h74riqs76erw24p5yvdhmwu7pxlcx4/STR_Logo_1.png",