In-App Payments SDK

What It Does

Square In-App Payments SDK provides a secure, managed payments client for Android, iOS, Flutter, and React Native applications. Use In-App Payments SDK to accept payment cards such as credit cards and digital wallets (Apple Pay and Google Pay) with a fully customized payment screen that seamlessly matches the branding of the application. For more information, see How It Works.


In-App Payments SDK produces a one-time use secure payment card token (nonce). Your backend Payments API code uses the nonce generated by the SDK to complete a payment.

In-App Payments SDK is available for native development on iOS and Android and as an open-source plugin for Flutter and React Native.


Requirements and limitations Permalink Get a link to this section

  • In-App Payments SDK requires a backend service to complete payments and issue refunds.

  • Using In-App Payments SDK to process digital goods, services, or subscriptions might not be allowed by some application distribution platforms.

  • In-App Payments SDK for Android requires the following OS permissions:

    • ACCESS_NETWORK_STATE to access information about networks.

    • INTERNET to open network sockets.

  • In-App Payments SDK for iOS does not require explicit OS permissions.

Payment source support varies by country. For more information, see Supported Payment Methods by Country.

In-App Payments SDK components Permalink Get a link to this section

In-App Payments SDK lets buyers enter their payment information on an entry screen instead of using a Square Reader to tap, dip, or swipe for payment. The SDK collects the payment information and generates a nonce (an encrypted payment token). Your application sends the nonce to your server, which uses the Payments API to capture the payment.

The following components make up an In-App Payments SDK payments solution:

  • Client side. A mobile application using In-App Payments SDK, which captures payment information and returns a valid nonce.

  • Server side. A web service using the Square Payments API , which accepts the nonce and sends charge requests to Square to process the payment.

    Did you know?

    If you already have an online payment solution that uses the Square payment form, you can leverage your existing server-side component to complete a payment with your in-app payment experience.

Trio of screenshots from the In-App Payments SDK Android sample app

The style of the card entry experience looks great out of the box but can be customized to match the hosting application. In-App Payments SDKs allow customization of fonts, colors, and backgrounds.

Try the In-App Payments SDK Quick Start to see the SDK in action.

Did you know?

In-App Payments SDK is supported in the Square Sandbox.

Related topics Permalink Get a link to this section