01 Installs are not the finish line
Whether a video made money is decided after the install. So that is where measurement has to reach.
Same install, very different value.
RevenueCat’s State of Subscription Apps 2026 (115,000+ apps) puts numbers on how much is decided after the download. Apps with a hard paywall (no free use, the trial or purchase gate comes first) convert trials to paid at a median of 10.7% by day 35. Freemium apps (a free tier with a paid upgrade) convert at 2.1%. Revenue per install at day 60: $3.09 against $0.38.
Same install, up to 8x difference in what it is worth. An install count tells you almost nothing about revenue, and it tells you nothing at all about which video the paying users came from.
Cheap trials are a trap of their own. RevenueCat’s creative-testing post warns that when a campaign optimizes for trial starts, some creatives show a low cost per trial and “very poor conversion to paid subscription afterward,” often because the platform over-delivers to 18 to 24 year olds who try apps and rarely subscribe.
A creative can win on installs, win on trials, and lose on revenue. Lesson 01 picked paid subscribers as the metric that gets the final vote. This lesson is what makes that metric exist.
| Video A | Video B | |
|---|---|---|
| Installs | 410 | 330 |
| Trial starts | 28 | 52 |
| Paid subscribers | 4 | 17 |
Everything below the first row is invisible until your app sends the events.
02 Two events, one path
Start Trial and Subscribe. Send them one way, not two.
Pick the SDK or RevenueCat. Both at once counts every purchase twice.
Airbridge tracks subscriptions with three standard events: Start Trial, Subscribe, and Unsubscribe. Subscribe fires on the first purchase, on a trial converting, and on each renewal. Revenue rides on Subscribe: send the amount and the currency with the event, flagged as revenue, and the report sums it.
Your app fires Start Trial when a trial begins and Subscribe when a purchase, a trial conversion, or a renewal completes, with amount and currency attached. Unsubscribe on cancellation.
If RevenueCat already handles your subscriptions, connect it and the mapping is fixed: trial started → Start Trial, initial purchase / trial converted / renewal → Subscribe, cancellation → Unsubscribe.
The condition that makes Path B work. The same user ID and device ID have to reach both RevenueCat and Airbridge, so the event lands on the install the Tracking Link brought in. Your developer will know what that means. The request card below says it for you.
Two limits to know before you promise anything
- This covers in-app purchases. Subscriptions sold through a web checkout page are outside what this setup measures.
- These are Airbridge’s standard events. You do not need, and on the Core Plan cannot add, a custom event for this.
How to see this in Airbridge
- Open Reports → Actuals.
- Add Start Trial, Subscribe, and Revenue next to Installs.
- Group by Ad Creative for one row per video, or Campaign for one row per creator.
You'll see:
each row read clicks → installs → trial starts → paid subscribers → revenue, for one video, one angle, or one creator.
03 The developer request
You do not have to explain this. Send the card.
One page, three decisions already made.
Your developer request
Pick how your app handles subscriptions. The request writes itself. Paste it into Slack, Linear, or an email.
01How do you handle subscriptions?
Request to send
Pick one to write the request.
While you wait. Keep posting? Better not. If the first videos are already live, the trial and paid columns for those videos will start from the day the events go in, not from the day the video did.
04 Confirm it’s flowing
You will know it worked when Start Trial and Subscribe appear in the metric list.
Airbridge only lists metrics it has actually received.
This is the one place the product is quietly helpful. The metric picker in Actuals shows only events that have been collected. So the check is not “does the number look right.” It is “is the metric there at all.”
- Developer confirmed the test purchase
- Start Trial appears in the Actuals metric list
- Subscribe appears in the Actuals metric list
- Revenue shows a non-zero value for the test purchase (amount and currency were sent)
- The test row is under the right creator and video (the link from Lesson 04)
If Subscribe is missing from the list, the event never arrived. Go back to the card, not to the report.
How to see this in Airbridge
- Open Reports → Actuals and open the metric picker.
- Look for Start Trial and Subscribe. If they are listed, the app is sending them.
- Add them, group by Ad Creative, and find your test purchase in the test video’s row.
You'll see:
the metrics that were missing last week, now sitting next to Installs, one row per video.