AdMob CMP — Compose Multiplatform AdMob SDK for Android and iOS

Quickstart · Ad formats · Compatibility · Showcase · Contributing

AdMob CMP is an open-source Kotlin Multiplatform SDK for Google AdMob in Compose Multiplatform apps. Use one commonMain API for banner, interstitial, rewarded, rewarded interstitial, app-open, and native ads on Android and iOS.

The SDK wraps Google Mobile Ads Next-Gen on Android and Google Mobile Ads on iOS while preserving familiar AdMob concepts such as AdValue, ResponseInfo, adaptive banner sizes, UMP consent states, and native asset names. Its shared API uses suspend functions, StateFlow state, and a sealed AdEvent stream, with consent, ATT ordering, paid events, and mediation integrated into initialization.

Documentation: ads.avinya.dev · What is AdMob CMP? · Quickstart · Installation · iOS setup · Troubleshooting

Coming from a hand-rolled expect class AdManager? See the migration guide.

// commonMain
implementation("dev.avinya.ads:admob-cmp:2.0.1")

plugins {
    id("dev.avinya.ads.admob-cmp") version "2.0.1"
}

Platform setup — the Android manifest entry, and on iOS the two Swift packages plus Info.plist keys — is required. Follow the Android setup and iOS setup guides, then verify with ./gradlew :admob-cmp-core:doctorIos.

All six formats, on both platforms, from one commonMain API.

This runs against Google's official sample ad units, so it is safe to paste as-is.

@Composable
fun App() {
    val adManager = rememberAdManager()

    LaunchedEffect(Unit) {
        adManager.gatherConsentAndInitialize(
            AdConfig(
                androidAppId = TestAdIds.ANDROID_APP_ID,
                iosAppId = TestAdIds.IOS_APP_ID,
                testMode = true
            )
        )
    }

    val placement = remember {
        AdPlacement(
            id = "main_interstitial",
            format = AdFormat.Interstitial,
            androidAdUnitId = TestAdIds.ANDROID_INTERSTITIAL,
            iosAdUnitId = TestAdIds.IOS_INTERSTITIAL,
            strictTestMode = true
        )
    }
    val interstitial = remember(adManager) { adManager.interstitial(placement) }
    val scope = rememberCoroutineScope()

    Button(onClick = {
        scope.launch {
            interstitial.load()
            interstitial.show()
        }
    }) { Text("Show ad") }
}

gatherConsentAndInitialize runs the whole production sequence for you: UMP consent, then App Tracking Transparency on iOS, then the one-time SDK initialization. Gate ad-dependent UI on adManager.status.collectAsState() reaching AdManagerStatus.Ready.

A banner is one composable — it measures its own container and supplies the width, so adaptive sizing is correct even in iPad split view and Slide Over:

BannerAdView(
    placement = AdPlacement(
        id = "home_banner",
        format = AdFormat.Banner,
        androidAdUnitId = TestAdIds.ANDROID_BANNER,
        iosAdUnitId = TestAdIds.IOS_BANNER
    ),
    modifier = Modifier.fillMaxWidth()
)

Native ads are laid out with a declarative DSL and served by a bounded session. A feed reuses one placement id, keeps stable model-owned slot keys, and lets the session own native platform objects:

val nativePlacement = remember {
    AdPlacement(
        id = "feed_native",
        format = AdFormat.Native,
        androidAdUnitId = TestAdIds.ANDROID_NATIVE,
        iosAdUnitId = TestAdIds.IOS_NATIVE,
    )
}

val layout = remember {
    adLayout {
        column(modifier = AdModifier.fillMaxWidth()) {
            media(modifier = AdModifier.fillMaxWidth().aspectRatio(16f / 9f))
            headline(maxLines = 2)
            body(maxLines = 3)
            row(spacing = 8.dp) { icon(modifier = AdModifier.size(24.dp)); advertiser(); adBadge() }
            callToAction(modifier = AdModifier.fillMaxWidth())
        }
    }
}

val session = rememberNativeAdFeedSession(
    sessionKey = "feed",
    listState = listState,
    itemCount = feed.size,
    slotAt = { index -> (feed[index] as? FeedItem.NativeSlot)?.let { NativeAdSlot(it.key, nativePlacement) } },
)
NativeAdView(session = session, slotKey = "after-article-3", placement = nativePlacement, layout = layout)

• Six formats, not four. Native ads and app-open ads are supported on both platforms, with a layout DSL and bounded, viewport-aware sessions.
• Consent is part of initialization. UMP modes, the privacy options form, and canRequestAds are first-class, and the iOS consent → ATT → initialize ordering is enforced rather than documented and hoped for.
• The iOS test link actually works. The dev.avinya.ads.admob-cmp Gradle plugin links Google Mobile Ads and UMP into Kotlin/Native test executables, which is the difference between :iosSimulatorArm64Test passing and failing with Undefined symbols … _OBJC_CLASS_$_GAD*.
• Revenue and mediation are exposed. Paid events carry AdValue and ResponseInfo; mediation adapters get initialization hooks.
• Test safety fails closed. AdPlacement.strictTestMode throws at construction if a placement points at a production ad unit — turn it on in debug builds.
• The public ABI is frozen and checked locally by ./scripts/release-readiness.sh, because CI does not run SDK or ABI verification.

admob-cmp publishes Kotlin/Native klibs plus cinterop klibs. Klibs are not binary-compatible across arbitrary Kotlin versions, so consumers must build with a compatible compiler.

Underlying Google SDKs bound by 2.0.1:

Kotlin: the module is compiled with 2.3.20. Consumers on a different Kotlin minor version may fail to resolve the klib. Patch versions are generally safe.

Compose Multiplatform: required only if you use the composable surface (BannerAdView, NativeAdView, rememberAdManager). The controller API in dev.avinya.ads:admob-cmp-core has no Compose dependency.

Consumption model: the SDK is consumable from Kotlin Multiplatform / Gradle projects only — it compiles into the consumer's umbrella framework. A pure-Swift iOS app cannot adopt it without a Kotlin Multiplatform shim.

Published artifacts: dev.avinya.ads:admob-cmp is the facade and is what you should depend on. It brings in dev.avinya.ads:admob-cmp-core (Compose-free) and dev.avinya.ads:admob-cmp-compose (the composables). dev.avinya.ads:admob-cmp-gradle-plugin is the Kotlin/Native test-linking plugin, applied by its dev.avinya.ads.admob-cmp plugin id.

Full guides, diagrams, and the generated API reference live at ads.avinya.dev.

• What is AdMob CMP? · Quickstart — a rendering test ad in five minutes
• Installation — Gradle, version catalog, and the Gradle plugin
• Android setup · iOS setup · Migrate from expect/actual
• Banner · Interstitial · Rewarded · App-open · Native
• UMP consent · App Tracking Transparency · Play Data safety
• Mediation · Revenue events · Caching, retry and timeouts · Test safety
• Architecture · Compatibility · Troubleshooting · Changelog
• Roadmap · Contributing · Using with AI agents
• Publishing — maintainer guide, repository only

Integrating with an AI coding agent? Point it at admob-cmp/AGENTS.md and https://ads.avinya.dev/llms.txt — the latter is the canonical, machine-readable bundle of the full site.

Android and iOS open directly into the AdMob debug console, which exercises every format against Google's official sample ad units with strictTestMode validation on every placement.

./gradlew :androidApp:assembleDebug          # Android
./gradlew :desktopApp:run                    # Desktop (no ads)
./gradlew :webApp:wasmJsBrowserDevelopmentRun # Web (no ads)

Tests:

./gradlew :admob-cmp-core:testAndroidHostTest        # JVM + Android-layer unit tests
./gradlew :admob-cmp-core:iosSimulatorArm64Test      # iOS unit tests
./gradlew :admob-cmp-core:checkKotlinAbi             # public API surface check
./gradlew :admob-cmp-core:doctorIos                  # diagnose iOS consumer integration

Issues are open for bugs and feature ideas. This repository runs no SDK tests in CI, by design — verification is local and is the contributor's responsibility. Before opening a PR, run ./scripts/release-readiness.sh and get a clean READINESS: PASS; a pass is a prerequisite for asking the owner to open the PR, not authorization to open it unilaterally.

Full contributor guide, including the public-ABI rules and the release procedure: CONTRIBUTING.md and ads.avinya.dev/project/contributing/.

showcase/ is a product-shaped Compose Multiplatform reference module named Fieldnotes. It exercises every ad format in real product flows — a chronological feed with interleaved native slots, section browsing, a rewarded coin economy, and an interstitial gated on natural transitions — with an in-app SDK Lab and telemetry Inspector. It is a consumer of admob-cmp; reusable ad lifecycle behavior belongs in the SDK, not in sample-only workarounds.

./gradlew :showcase:testAndroidHostTest :showcase:iosSimulatorArm64Test :showcase:compileKotlinIosSimulatorArm64 --no-configuration-cache

Full destination tour, format-coverage table, and the Telemetry Inspector: ads.avinya.dev/project/showcase/.

Apache License 2.0.

Not affiliated with or endorsed by Google. AdMob and Google Mobile Ads are trademarks of Google LLC.