---
title: Android quickstart
description: Add the Extentos Android SDK by hand — Gradle install, manifest permissions, and your first capability call. Voice apps need no vendor token.
type: tutorial
platform: android
related:
  - /docs/sdk/android
  - /docs/getting-started/with-agent
---

The by-hand path for adding Extentos to an existing Android app. Prefer letting an agent do the wiring? Use the [agent-driven quickstart](/docs/getting-started/with-agent) — same outcome, less typing. Each step below links to the SDK reference for full detail.

## 1. Add the dependencies

`com.extentos:glasses` + `com.extentos:glasses-ui` are on Maven Central and carry **no vendor dependency** — nothing else to declare, no token.

```kotlin title="app/build.gradle.kts"
android {
    buildFeatures {
        // AGP 8 defaults this OFF, and the init snippet below reads
        // BuildConfig.DEBUG. Without it, step 3 does not compile.
        buildConfig = true
    }
}

dependencies {
    implementation("com.extentos:glasses:2.1.2")
    implementation("com.extentos:glasses-ui:2.1.2")   // optional — the prebuilt connection page

    // The SDK's suspend surface needs a dispatcher from your side.
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.9.0")
}
```

That's everything a **voice app** needs to build. If your app uses the **camera or the display**, add the Meta vendor module too — it brings the Meta DAT artifacts, which live on Meta's GitHub Packages and need a `read:packages` token:

```kotlin title="app/build.gradle.kts"
    implementation("com.extentos:glasses-meta:2.1.2")
```

The extra repo block + token setup + toolchain floors are in [Install the Android SDK](/docs/sdk/android/install). Not sure which you need? [Choose your path](/docs/getting-started/choose-your-path).

Floors: `minSdk 31`, `compileSdk 35`, Kotlin `2.1.20`, AGP `8.6+`, Gradle `8.7+`, JVM 17. You also need `namespace` set in your `android { }` block — AGP 8 fails the build without it.

One more thing before you ship a voice app that uses the assistant: bake your **project key**, or the assistant won't reach the managed gateway from a sideloaded build. It's one line, it never causes a build error, and its absence shows up only at runtime as `AssistantError.NoApiKey`:

```kotlin title="app/build.gradle.kts"
android {
    defaultConfig {
        buildConfigField("String", "EXTENTOS_PROJECT_KEY", "\"pk_your_project_key\"")
    }
}
```

`generateConnectionModule` mints the key and emits this line; wiring by hand, take it from your dashboard project. Detail: [install § the project key](/docs/sdk/android/install).

## 2. Declare permissions

The library auto-merges the Bluetooth + service entries; you add the **capability** permissions your app uses — `CAMERA`, `RECORD_AUDIO`, `INTERNET`, and (for background mic) `FOREGROUND_SERVICE` + `FOREGROUND_SERVICE_MICROPHONE`. Which capability needs which: [Manifest setup](/docs/sdk/android/manifest) and [Permissions](/docs/concepts/permissions).

## 3. Initialize Extentos

Create one `ExtentosGlasses` for your app's lifetime:

```kotlin
val glasses = ExtentosGlasses.create(
    ExtentosConfig(
        applicationContext = applicationContext,
        environment = if (BuildConfig.DEBUG) ExtentosEnvironment.DEVELOPMENT else ExtentosEnvironment.PRODUCTION,
    )
)
```

`TransportChoice.Auto` (the default) picks the browser simulator during development, real glasses when a vendor module claims one, and otherwise the system-audio baseline — mic and speaker over whatever the OS routed, so a voice app works on a phone with nothing paired. Config table + lifecycle: [Initialization](/docs/sdk/android/initialization).

## 4. Make your first capability call

Capability calls return `ExtentosResult` — pattern-match, don't `try/catch`:

```kotlin
when (val r = glasses.camera.capturePhoto()) {
    is ExtentosResult.Ok  -> showPhoto(r.value)
    is ExtentosResult.Err -> handle(r.error)   // CaptureError
}
```

Per-primitive snippets come from the [`getCapabilityGuide`](/docs/mcp-server/tools/discovery) MCP tool; full flows from [`getCodeExample`](/docs/guides). For voice AI, the Phase-4 [assistant runtime](/docs/guides/voice-assistant) is the canonical path (stable since `1.4.0`).

## 5. Verify in the browser simulator

Run your app against the [browser simulator](/docs/concepts/transport-vs-app) — the same library code, only the transport swapped. Mint a session with the `createSimulatorSession` MCP tool (or from [extentos.com/s](https://extentos.com/s)); the running app auto-attaches via the local bridge. Watch capability events flow with [`getEventLog`](/docs/mcp-server/tools/simulation).

## Next

- [Android SDK reference](/docs/sdk/android) — install, manifest, init, lifecycle, threading, runtime internals
- [Guides](/docs/guides) — task-shaped recipes (voice, photo, video, display, …)
- [From simulator to real glasses](/docs/guides/simulator-to-real-glasses) — the hardware transition