# Playtesters > Official platform & client SDKs for Android closed-testing groups (Google Play 20-tester requirement). Playtesters (https://playtesters.dev) is a peer-to-peer closed-testing platform for mobile developers. It connects developers to test each other's apps for free, validating real device sessions via drop-in client SDKs (Flutter, React Native, Native Android) and Google Play Install Referrer verification. ## Core Resources - [Landing Page](https://playtesters.dev): Overview and live interactive SDK simulator. - [Web Dashboard](https://app.playtesters.dev): Manage apps, campaigns, logs, and peer testing groups. - [Full Context Documentation](https://playtesters.dev/llms-full.txt): Complete SDK integration guides, code samples, and API specifications. - [Privacy Policy](https://playtesters.dev/privacy): Privacy policy and data handling practices. - [App-Ads.txt](https://playtesters.dev/app-ads.txt): Authorized Digital Sellers (IAB Tech Lab) ad verification file. ## Client SDKs - [Flutter SDK](https://pub.dev/packages/playtesters_sdk): `playtesters_sdk` on pub.dev. Supports Flutter on Android and iOS. - [React Native SDK](https://www.npmjs.com/package/@playtesters/react-native-sdk): `@playtesters/react-native-sdk` on npm. - [Android Native SDK](https://jitpack.io/#alexcao194/playtesters_sdk): `com.github.alexcao194:playtesters_sdk` on JitPack. ## Key Features & Protocol - **Peer-to-Peer Closed Testing**: Developers join groups of 20 members to reciprocal-test apps for 14 continuous days. - **Genuine Session Verification**: Captures `code`, `locale`, and `playtesters=1` from Google Play Install Referrer on first open, preventing fabricated test days. - **Milestone Tracking**: Host applications invoke `achieved()` to verify daily user progression. - **Android App Links**: Deep links via `https://playtesters.dev/invite/{code}` automatically route testers directly to join campaigns.