# Overview (/docs/sdk)





The **Layers SDK** instruments your app so Layers can attribute installs to the campaigns that drove them and measure what users do afterward. You install it once per platform, initialize it with your **App ID**, and call `track()` for the events you care about — the SDK handles sessions, batching, and attribution for you.

<Callout type="info">
  This is the **client SDK** — the code you ship inside your app. If you're
  building against Layers from a backend and want HTTP endpoints instead, see the
  [API integration](/docs/api). If you can't ship a client SDK at all, you can
  forward events server-side with [`POST /v1/events`](/docs/api/reference/events/forward).
</Callout>

## Supported platforms [#supported-platforms]

| Platform         | Package                          |
| ---------------- | -------------------------------- |
| Expo             | `@layers/expo`                   |
| React Native     | `@layers/react-native`           |
| iOS (Swift)      | `layers-sdk-ios` (Swift Package) |
| Android (Kotlin) | `io.layers.sdk:layers-android`   |
| Flutter          | `layers_flutter`                 |
| Web              | `@layers/client`                 |
| Node.js          | `@layers/node`                   |

## Get your App ID [#get-your-app-id]

Every install is initialized with an **App ID** — a stable identifier for one app in one project. Find it in the Layers app: open your project's **Events** screen, click the **gear icon**, and copy the value under **App ID**. The same App ID is returned by [`GET /v1/projects/:projectId/sdk-apps/:appId`](/docs/api/reference/sdk-apps/get-sdk-app).

In the snippets throughout this section, replace `YOUR_APP_ID` with that value.

## Next steps [#next-steps]

<Cards>
  <Card icon="<Rocket className=&#x22;text-fd-primary&#x22; />" title="Installation" href="/docs/sdk/installation" description="Per-platform setup — install the package, initialize with your App ID, send your first event." />

  <Card icon="<Bot className=&#x22;text-fd-primary&#x22; />" title="Prompt your coding agent" href="/docs/sdk/agent-prompt" description="A ready-to-paste prompt that has Claude, Cursor, or any agent instrument your app." />

  <Card icon="<Radio className=&#x22;text-fd-primary&#x22; />" title="Tracking events" href="/docs/sdk/tracking-events" description="The events worth tracking, their properties, identifying users, and how batching works." />

  <Card icon="<Fingerprint className=&#x22;text-fd-primary&#x22; />" title="Attribution" href="/docs/sdk/attribution" description="How installs are attributed, plus iOS clipboard attribution and App Tracking Transparency." />
</Cards>

## Verify it's working [#verify-its-working]

Once the SDK is initialized and sending data, confirm the signal on the same **Events** screen in the app — you'll see events stream in and a live status indicator. For a programmatic check (including an active synthetic probe), see [SDK health & verification](/docs/api/concepts/sdk-health).

## Automated install [#automated-install]

If your project is connected to a GitHub repository, Layers can open a pull request that wires the SDK into your codebase for you. Trigger it from the **Installation** panel of the Events gear in the app — the manual steps in this section are what that PR automates.