Firebase / GA4

The Firebase / GA4 integration forwards Rovenue revenue events (purchases, trial conversions, renewals, refunds, cancellations) and subscription-lifecycle events (trials, grace period, billing issues, plan changes) to a Firebase app stream via the GA4 Measurement Protocol, so subscription behavior shows up alongside the rest of your Firebase Analytics / BigQuery export data.

Scope note — Firebase app streams only. This integration authenticates with firebase_app_id, which only works for a Firebase app stream (an iOS/Android/Unity app registered in a Firebase project). A GA4 web stream — authenticated with measurement_id + a browser client_id instead — is a different Measurement Protocol contract and is a documented non-goal for this wave. If you need to forward events to a GA4 web property, use the Custom Webhook provider and adapt the payload yourself.

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1. Get your credentials from Firebase and Google Analytics

1. In the Firebase console, open Project settings → General and copy the App ID for the specific app (iOS/Android) you want events attributed to — this is firebase_app_id. It looks like 1:1234567890:android:abc123 or 1:1234567890:ios:abc123.
2. In Google Analytics (the GA4 property linked to that Firebase project), open Admin → Data Streams, select the Firebase app stream, then Measurement Protocol API secrets.
3. Click Create to mint a new secret and copy it — this is api_secret.

The Measurement Protocol API secret only grants event-ingestion write access to this one data stream; it is not a full Google Analytics credential.

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2. Add the integration in Rovenue

1. In the Rovenue dashboard, navigate to Apps (left sidebar).
2. Find Firebase / GA4 under Product analytics and click it.
3. The side drawer opens. Fill in the Credentials step:
   • Measurement Protocol API secret — from step 1.
   • Firebase app ID — from step 1.
4. Click Validate — Rovenue POSTs a minimal, clearly-tagged probe event to GA4's validation server (/debug/mp/collect), which per Google's own docs does not count toward your reports, and fails the check if GA4 reports any validationMessages.
   • Caveat, straight from Google's docs: the validation server does not verify that api_secret or firebase_app_id are actually correct — only that the event body is well-formed. A well-formed but wrong secret/app-id pair still passes Validate. Double-check both values against the Firebase console / GA4 Admin screen.
5. Choose which events to forward, optionally override the default vendor event names, then activate.

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3. Event mapping

GA4 constrains custom event names to the regex ^[A-Za-z]\w*$ (must start with a letter; letters, digits, and underscores only — no dots or hyphens). Rovenue's public event keys are forwarded as your GA4 event name, using the following default names (overridable per-connection in the drawer's mapping step):

Unlike Amplitude/Mixpanel's free-form event names, four distinct Rovenue revenue keys (INITIAL/RENEWAL/TRIAL_CONVERSION/CREDIT_PURCHASE) all collapse onto GA4's own recommended purchase event — GA4 has no separate vocabulary to distinguish an initial purchase from a renewal. Every subscription-lifecycle key is instead sent as a rovenue_-prefixed custom event, since GA4 has no standard vocabulary for subscription lifecycle at all.

Every forwarded event carries params.rovenue_event set to the original Rovenue event key (e.g. revenue.RENEWAL), so you can always trace a GA4 event back to its Rovenue source regardless of how the vendor event name has been overridden, plus params.product_id and params.transaction_id.

Revenue fields

For the six revenue.* keys only, Rovenue also populates params.value and params.currency. Subscription-lifecycle events never carry these fields — they represent no money movement.

revenue.REFUND is sent with a POSITIVE value, alongside the distinct refund event name — this is the opposite convention from Amplitude/Mixpanel (which negate the amount and reuse a generic event name). GA4's own documented refund model represents a refund as its own refund event carrying the positive amount being refunded; GA4 nets this against prior purchase events server-side when computing revenue metrics. Rovenue's internal ledger always stores refund amounts as positive, so no sign flip happens at this wire boundary (unlike Amplitude/Mixpanel).

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4. Identity resolution

Every event requires GA4's app_instance_id — the Firebase Analytics SDK's own per-install identifier. There is no fallback chain here (unlike Amplitude/Mixpanel's appUserId/subscriber-id fallbacks): GA4's Measurement Protocol for a Firebase app stream has no concept of an arbitrary user id, so Rovenue cannot substitute anything else and land the event against the correct GA4 user.

Set the $firebaseAppInstanceId subscriber attribute from your app using the Firebase SDK's own instance-id accessor (e.g. Analytics.appInstanceID() on iOS, FirebaseAnalytics.getAppInstanceId() on Android), then call the Rovenue SDK's setAttributes. See Subscriber Identity Attributes for the full reserved-attribute reference.

If $firebaseAppInstanceId is not set, the event is skipped with reason no_user_data (visible in the connection's Delivery Log).

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5. Deduplication

Every forwarded event carries params.transaction_id set to Rovenue's internal outboxEventId. GA4 uses transaction_id to dedup repeated purchase/refund events, so retries after a network failure or an at-least-once outbox replay do not double-count revenue.

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6. Verify events are arriving

1. Open DebugView in Google Analytics (Admin → DebugView), or wait for the event to appear in standard GA4 reports (can take up to 24 hours outside DebugView).
2. Trigger a real event from your app (a renewal, a trial start, etc.).
3. If events are not appearing:
   • Re-check api_secret and firebase_app_id directly against the Firebase console / GA4 Admin screen — remember, Validate does not catch a wrong-but-well-formed pair (see the caveat in step 2).
   • Check Apps → Firebase / GA4 → Delivery Log in Rovenue for HTTP status codes and error messages. Note that GA4's live collect endpoint (/mp/collect) returns success codes even for a malformed event body — a "successful" delivery in the log does not by itself prove the event was accepted by GA4's processing pipeline.
   • Ensure the event type you're sending is included in the connection's enabled events.
   • Ensure the subscriber has $firebaseAppInstanceId set — without it, events are skipped before ever reaching GA4.