Stop invalid traffic on mobile app retargeting campaigns

On Android, malicious apps installed on the user's device can detect when the user opens a specific app and fire an invalid retargeting click at that moment. Because the click appears immediately before the app session in the attribution window, your MMP credits the invalid retargeting source with the re-engagement. The user was going to open the app anyway. The operation has simply inserted itself into the attribution chain to extract a re-engagement payout for an action it did not drive.

Click injection in its classic form is primarily an Android vulnerability because it exploits Play Store install broadcasts. On iOS, retargeting abuse more commonly takes the form of click stuffing and timing manipulation, where invalid publishers flood your retargeting tracking links with clicks timed to coincide with known periods of organic user return. Tapper monitors both platforms and applies the relevant detection models for each.

When invalid sources claim credit for organic re-engagements, your data overstates how many lapsed users are responding to retargeting and understates natural organic return rates. This distorts cohort-level analysis of which user segments are naturally sticky versus which genuinely respond to re-engagement prompts. Budget and creative decisions based on this data will consistently misallocate retargeting spend.

Networks that rely on third-party publisher ecosystems for retargeting reach, rather than direct inventory, carry the highest risk. In-app advertising placements used to serve retargeting ads on smaller networks are common vectors for click injection. Tapper monitors all retargeting partners you connect and surfaces which sources show anomalous click patterns so you can adjust spend and exclusion lists accordingly.

Your reported re-engagement count will fall to reflect only genuine user returns driven by your campaigns. Your retargeting ROAS may initially look lower because the denominator of claimed re-engagements is smaller. However, because invalid re-engagements were not generating real app sessions or revenue, your actual business outcomes do not change. The ROAS figure you see after removing invalid traffic is an accurate reflection of what your retargeting spend is actually producing.

Tapper combines CTIT analysis, click velocity measurement, publisher behavioral scoring, and session validation to classify re-engagement clicks. Invalid clicks show characteristic patterns: they arrive in tight clusters around known organic re-engagement windows, they originate from publishers with abnormal click-to-session ratios, and they exhibit timing precision inconsistent with human interaction. Legitimate retargeting clicks show natural variation in timing and are distributed across session windows rather than concentrated immediately before app opens.