> For the complete documentation index, see [llms.txt](https://docs.coda.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.coda.co/coda-links/link-users-out-to-coda-powered-webstore/link-to-webstore-checkout-on-android-us.md). # Link to Webstore checkout on Android - US 🇺🇸 To successfully launch Coda Links on Android for users in the United States, developers must comply with Google's External Content Link (ECL) program. Standard hyperlinks are no longer permitted; developers must use Google's designated ECL APIs by the enforcement deadline of **January 28, 2026**. {% hint style="info" %} **Requirement summary** * **Mandatory API Integration:** Developers cannot simply put a "naked" hyperlink in the app. They must integrate with Google's External Content Links APIs, through which Google enforces transaction tracking and controls the linkout UX. * **Controlled User Experience:** When a user clicks an external link, this API triggers a system-level information screen (a "warning" or "interstitial") that informs the user they are leaving Google Play and completing a transaction outside the Play billing system. The user must click to confirm in order to proceed. * **Transaction Reporting**: Google indicated that external transactions and downloads may be subject to reporting requirements once service fees are activated. Thus, **implementation work related to Transaction Reporting is currently not required in the US.** Refer to this official page for the latest information on Google's requirements & fees:\ **Play Console Help >** [**Enrolling in the external content links program for users in the US**](https://support.google.com/googleplay/android-developer/answer/16470497) {% endhint %} Below is the step-by-step integration guide for linking users to your Coda Webstore, based on Google's ECL requirements: ## Prerequisites Ensure that you have followed the [Steps to Launch your Web Store](/coda-webstore/steps-to-launch-your-web-store.md), and published your Coda Webstore. This is the standard integration that allows users to purchase items on the web store and have the items fulfilled in-game. If you already have this set up with Coda, no further modifications are required. ## Step 1: Program Enrollment on Play Console Before integrating the APIs, you must establish the necessary contractual ties and permissions with Google: 1. Complete Google’s [**External Content Links Declaration Form**](https://support.google.com/googleplay/android-developer/contact/external_content_links?sjid=13187887999033167618-NC) and any required onboarding steps with Google's support team. 2. In the Google Play Console, navigate to **Settings > External content links** to officially enroll the app(s) that will use Coda Links. Next, let's explore the technical details for implementation ## Flow Overview
## Step 2: Construct the URL & link users out from your Android App 1. **Update Play Billing Dependencies:** Add or update the **Play Billing Library** to **version 8.2.1 or higher** in your Android app. If migrating from an older version, follow Google's official migration guide first. 2. **Check Availability:** Programmatically call `isBillingProgramAvailableAsync()` to verify the program is available on the device. 3. **Generate a Transaction Token:** When the user clicks a link/button that should take them to out-of-app, before redirecting the user, call `createBillingProgramReportingDetailsAsync()`. This generates a unique `externalTransactionToken`. > **Note:** You must generate a new `externalTransactionToken` every single time a user attempts to visit the external web store (i.e every click) 4. **Construct the checkout URL:** Build the destination URL dynamically. It must append your `externalTransactionToken` alongside the standard Coda parameters. Your final URL should include: * `mode` (e.g., `mode=lite` tells your webstore that this is a linkout purchase, and to trigger the express checkout flow for maximum conversion-friendliness) * `sessionToken` (for extracting the user's UID/account. The Coda webstore uses this information to validate the checkout with your server, and ensure item delivery is made to the right user.) * `skuId` (the specific item selected, exactly as configured on the Coda webstore) * `utm` parameters (source, medium, campaign) * `externalTransactionToken` (the token generated in Step 3) For example: ``` https://store.mygame.com/en-us ?mode=lite &sessionToken=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJPbmxpbmUgSldUIEJ1aWxkZXIiLCJpYXQiOjE3NzA2MDI5MjksImV4cCI6MTgwMjEzODkyOSwiYXVkIjoid3d3LmV4YW1wbGUuY29tIiwic3ViIjoiU0hfVVNBIiwiR2l2ZW5OYW1lIjoiSm9obm55IiwiU3VybmFtZSI6IlJvY2tldCIsIkVtYWlsIjoianJvY2tldEBleGFtcGxlLmNvbSIsIlJvbGUiOlsiTWFuYWdlciIsIlByb2plY3QgQWRtaW5pc3RyYXRvciJdfQ.-ui2BeK9zOdeIfeKUvJ0GS4oQioX964VTMztI31wmTQ &skuId=SKU001 &utm_campaign=usLinkout &utm_medium=codaLinks &utm_source=myapp &externalTransactionToken=1075cadc-e143-4ab6-acf3-a30bcf3bcbfc ``` 5. **Launch the Link:** Pass your constructed URL into the `launchExternalLink` method, with the `externalTransactionToken` and set the LaunchMode (which typically opens the URL in an external browser) > **User Experience:** Google will automatically intercept this call and display a mandatory system-level warning sheet (interstitial) informing the user they are leaving Google Play, which the user must confirm to proceed to checkout. ## Step 3: Post-Purchase UX & Deep Linking 1. **Item Fulfillment:** When the payment succeeds, Coda Webstore completes the payment and automatically sends a server-to-server item fulfillment request to your backend. This should already be covered in [Steps to Launch your Web Store](/coda-webstore/steps-to-launch-your-web-store.md). No change is required here.
2. **User can click to go back to App via deep link:** \ To ensure this redirection happens smoothly, you must provide Coda with a deep link that can redirect users back to your Android app upon a successful purchase. * Once the user is deep-linked back to your app, they should seamlessly receive their items. In addition, your app can display a purchase success screen with confetti animations! * Refer to [Redirecting users from Coda Links back to your app](/coda-links/redirecting-users-from-coda-links-back-to-your-app.md)to learn how to setup back-to-app redirection correctly for your Android App. 3. **User can explore Webstore's offers & LiveOps campaigns!** \ If you configure any of the Webstore LiveOps offers in [Commerce LiveOps](/coda-webstore/commerce-liveops.md), the post-purchase screen will display them to the user, encouraging them to explore & become a loyal webstore user {% hint style="success" icon="seedling" %} **Why having LiveOps features on Coda Links is crucial for your long-term revenue** * **Linkouts are not (actually) free:** Including in the US, Google and Apple are fighting tooth and nail to impose fees on external purchases to protect their revenue streams. For instance, Google charges up to a 20% commission on purchases made within 24 hours of a user following an external payment link. Similarly, Apple imposes a 15% commission on website sales initiated within 7 days of an end user tapping an out-of-app link. If users stick exclusively to linkout payments directly from the app, publisher margins will continuously be undercut by these fees with no way out. * **Webstore loyalty builds long-term profitability:** Converting purchasers from in-app to webstore should be the ultimate goal. Publishers can use elements on the linkout success page to convert users into direct webstore customers, which makes the long-term cost per transaction significantly lower. When users build a habit of going directly to out-of-app channels like a webstore, they bypass the in-app link altogether. These direct visits make their future purchases completely out-of-reach for the app platforms, meaning all fee savings go straight to the publisher's bottom line. {% endhint %} ## Step 4: Report external transactions to Google (not yet required) {% hint style="info" icon="exclamation" %} This is part of the Transaction Reporting requirement. They are not required at the time of writing this article. These steps are **only required when Google activates fees** for the [External Content Links Program for users in the US](https://support.google.com/googleplay/android-developer/answer/16470497) {% endhint %} Because developers remain the contracting party for external transactions, Google currently requires an infrastructure for **transaction reporting**, which will be activated only if/when Google implements service fees. 1. **Receive the Callback:** When a user successfully completes a purchase on the Coda checkout page, Coda will send a server-to-server top-up request to your backend. This payload will contain the `externalTransactionToken` that you originally passed in the URL, along with the payment confirmation data. 2. **Report external transactions to Google (not yet mandatory):** Upon receiving the top-up confirmation, your backend must call the **Google Play Developer API** (`externalTransactions` endpoint). You have **24 hours** to report the transaction by passing both the final sale amount and the `externalTransactionToken` back to Google. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.coda.co/coda-links/link-users-out-to-coda-powered-webstore/link-to-webstore-checkout-on-android-us.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.