If you’ve just started buying mobile traffic, don’t panic—measuring results after the big privacy change is easier than it sounds.
1. Use the new on-device Attribution Reporting API
Think of it as a tiny accountant that lives inside every Android 15 phone. When someone taps your ad and later completes an event (like “open” or “purchase”), the phone links the two right on the device and then sends you a delayed, privacy-safe report. No user ID ever leaves the handset, but you still know which campaign worked.
2. Read the aggregated summaries for true ROAS
Besides single-event reports, the same API can bundle hundreds of conversions into a “bucketed” file: installs, revenue tiers, even LTV groups. Pair those buckets with your spend numbers and you’ve got a clean profit-and-loss view—without personal data.
3. Keep Play’s Install Referrer tag in your toolbox
Google Play still adds a signed referrer string to every store install. In Android 15 that string now also carries the very first Device Token. Save it the moment your app launches and you can build cohorts (day-1 retention, ARPU, etc.) exactly like you did with GAID.
4. Feed your events straight back to OEM ad consoles
Manufacturers such as Xiaomi and Transsion already let you push “in-app events” (registration, level-2, purchase) into their dashboards. They’ll switch from GAID to Device Tokens behind the scenes, so you can still see which placements bring real users—no extra work.
5. Check Device Integrity tokens to block fraud
A new Play API lets you ask the phone “are you rooted, cloned, or running from a farm?” It answers with a yes/no token you can attach to every conversion. Drop the shady ones before they poison your KPIs.
6. Run geo or cohort lift tests
If IDs are shorter-lived, use geography (e.g., Brazil vs. Argentina) or handset brands (Samsung vs. Xiaomi) as natural test cells. Hold back 10 % of budget in a “dark” region, then compare installs and revenue that the Attribution API reports. Any gap is your true incremental gain.
7. Build simple token-level lifetime-value scores
A Device Token is unique inside your app, so treat it like a loyalty card number. Log sessions, purchases and churn flags against it. Every 30 days, when the token rotates, refresh the score.