Every app vertical needs a different event list, because every vertical delivers value at a different moment. A fintech app has not activated a user until money moves. A game has not activated a player until the tutorial is done. A dating app has not activated anyone until their profile can be matched. Copy one generic list across all of them and you will optimise campaigns toward the wrong users.
This page is the index for our event series. Each row below links to a full guide for one vertical.
What is a critical event?
A critical event is an in-app action that separates users who will create value from users who will not, early enough to steer ad spend. Installs, sessions and screen views tell you someone opened the app. Critical events tell you whether they reached the point where the product works for them.
Capturing them is the job of post-install event tracking: you fire the event in the app, your MMP ties it back to the campaign that drove the install, and you judge each campaign on events rather than install volume.
The activation event is the most important of these. It is the first action that reliably predicts retention, and it is the one you should report cost against first. Our activation rate analysis shows why: two apps with the same CPI can pay very different amounts per real user.
Critical events by vertical
| Vertical | Must-track events | Activation event | Full guide |
|---|---|---|---|
| Dating and community | Profile completed, first match, message reply received | Profile completed (an incomplete profile cannot be matched) | 7 events for dating and community apps |
| D2C brands | First purchase, subscription activated, repeat purchase within 60 days | First purchase | 7 events for D2C brand apps |
| Travel | Search performed, dates selected, first booking completed | First booking completed | 7 events for travel apps |
| OTT and streaming | First video played, binge session, premium subscription started | First video played | 7 events for OTT apps |
| Mobile gaming | Tutorial completed, level 5 reached, first in-app purchase | Tutorial completed | 7 events for mobile games |
| eCommerce | Add to cart, checkout started, first purchase completed | First purchase completed | 7 events for eCommerce apps |
| EdTech | First lesson started, first lesson completed, 3-day streak achieved | First lesson completed | 7 events for EdTech apps |
| Fintech | KYC completed, first deposit, first transaction | First deposit | 10 events for fintech apps |
Marketplaces are not in the event series yet. The eCommerce list is the closest fit for the buyer side, and the marketplace metrics guide covers how to measure seller activation separately.
Why one generic event list fails
The guides share a structure, but the funnels underneath them do not.
- Where value lands differs. Dating apps deliver value at a first match, OTT apps at a first video, EdTech apps at a completed lesson. A purchase-shaped template has no slot for any of them.
- Intent shows up in different places. In travel, selecting dates is a stronger signal than five app opens. In eCommerce, starting checkout separates buyers from browsers. In fintech, completing KYC separates curious users from users who can transact at all.
- Quality signals are vertical-specific. A dating campaign that drives matches without replies is driving low-quality users. A game campaign that drives tutorial completions without anyone reaching level 5 has not found players who like the core loop.
- Time to value differs, so windows differ. The guides use different attribution windows: 7 days for dating, 7-day click and 1-day view for eCommerce, 14 days for EdTech trial-to-paid journeys, 7 to 30 days for fintech, and 30 to 90 days for travel, where search to booking can take weeks.
How to use these lists together
Most teams do not need all seven (or ten) events on day one. Work through them in this order:
- Pick your activation event first. Use the row for your vertical, check it against your own data, and make it the first event your engineers ship.
- Add the two events either side of it. One intent signal before activation (dates selected, add to cart, KYC completed) and one depth signal after it (binge session, 3-day streak, repeat purchase). That gives you a three-step funnel per campaign.
- Send the activation event to ad networks. Map it as a conversion so Meta and Google optimise toward activated users, not installs.
- Report cost per activated user by channel. Then layer in revenue events and track retention rate by acquisition source.
- Borrow from neighbouring verticals. A D2C brand with a subscription product can reuse the OTT subscription events. A fintech app with a learning feature can reuse EdTech streak logic.
If you are still deciding what to measure before you spend, start with a measurement plan, then use our event taxonomy guide to name and structure the events consistently.
Events feed metrics: the companion hub
Events are the raw inputs. Metrics are what you calculate from them: first deposit and first transaction become a fintech activation rate, tutorial completion and first in-app purchase become a game's install-to-purchase rate, and first match feeds a dating app's match rate.
Our companion page, App Metrics That Matter, by Vertical, maps the north-star metric and key metrics for the same verticals, plus marketplaces. Each event guide also links to its matching metrics guide.
FAQ
What is the most important event for a mobile app to track? The activation event: the first action that reliably predicts a user will stay. It differs by vertical, for example first deposit in fintech, first video played in OTT and tutorial completed in gaming.
How many in-app events should we track at launch? Start with three: your activation event, one intent signal before it and one depth signal after it. Add revenue and retention events once those are reliable. The guides above list seven events per vertical (ten for fintech) as the full set.
Should we send every event to Meta and Google? No. Send the events you want the ad network to optimise toward, usually the activation event and a revenue event. Sending too many dilutes the signal.
Can two verticals share an event list? Partly. Commerce apps share the cart and purchase events, and subscription apps share trial and subscription events. The activation event is where they differ most, so do not copy that one.
How long does it take to set up event tracking with Linkrunner? Same day for most teams, fully live within a week. The SDK captures installs and sessions automatically, and custom events are added through the SDK's event API.