Short answer: the Google Play Install Referrer only exists for installs from Google Play. Installs from other Android stores, sideloaded APKs or adb have no Play referrer, so MMPs lose their main Android matching signal. Use the store's own referrer if it offers one, or link-based matching.
Why non-Play installs lose attribution
Install Referrer: information Google Play passes to an app on first launch describing the link that sent the user to the store listing, read through the Install Referrer library.
Android's Install Referrer library retrieves this data from Google Play. Google Ads' help centre says installs from third-party Android stores are recorded on first open and recommends Firebase for them, which implies no Play referrer is available. Android's own referrer docs do not discuss non-Play installs.
Do these installs count at all?
Yes. Your MMP still records the install when the app opens; it simply cannot tie it to a click through the Play referrer, so it usually lands in organic unless another matching method applies.
Likely causes
- Installed from a third-party store. No Google Play referrer exists for the install.
- Sideloaded APK. Same result.
- Debug builds installed with adb. Test installs from a developer machine have no Play referrer (general practice).
- Store-specific referrer not integrated. Some stores offer their own referrer mechanism, which needs separate integration (general practice).
How to confirm it
- Pull the installer package or store source for the unattributed Android installs.
- Compare attribution rates for Play and non-Play installs.
- For test devices, reinstall from a Play testing track and check whether attribution works.
- Check whether your MMP supports any of the other stores your app is listed in.
How to fix it
- Test attribution only with builds installed from Google Play testing tracks.
- Integrate the referrer mechanism of any other store you rely on, if it has one (general practice).
- Use link-based matching for campaigns that send users to other stores (general practice).
- Report non-Play installs as a separate segment so they do not distort organic.
| Install source | Play referrer | Usual MMP result |
|---|---|---|
| Google Play | Yes | Matched for same-session clicks |
| Other Android store | No | Organic unless store referrer integrated |
| Sideloaded APK | No | Organic |
| adb debug build | No | Organic |
The Play Install Referrer guide explains the referrer in detail, and the install referrer troubleshooter starts with this check. If Play installs are also unattributed, see paid installs showing as organic.