Last-Click Attribution

Last-click attribution is the default mobile attributionGlossaryInstall AttributionThe process of assigning credit for a new install to the ad, campaign, and network that drove it — so advertisers know what's working and can compensate networks acc... model. The rule is simple: the user's final ad click before install (within the configured attribution windowGlossaryAttribution WindowThe time period after an ad click or impression during which an install will still be credited to that ad — the lookback window that defines what counts as "caused b... — typically 7-30 days) gets 100% of the install credit. If a user clicked a TikTok ad on day 1 and a Meta retargetingGlossaryRetargetingPaid advertising targeted at users who already installed your app — typically aimed at re-engaging lapsed users or driving specific in-app actions. ad on day 5 then installed on day 7, the install goes to Meta. TikTok gets no credit, even though they may have created the original awareness.

Why last-click is the industry default

• Unambiguous — exactly one ad gets credit. No partial-credit math.
• Easy to implement — every MMPGlossaryMobile Measurement Partner (MMP)A third-party attribution provider (AppsFlyer, Adjust, Singular, Branch, Kochava) that adjudicates which ads drove which installs across multiple ad networks, with i... supports it natively. Default configuration in AppsFlyer, Adjust, Singular, Branch.
• Aligns with platform attribution — Meta, TikTok, Google all default to last-click within their own ecosystems.
• Communicates clearly — UAGlossaryPaid UA (Paid User Acquisition)Mobile app user acquisition via paid advertising channels — Meta, TikTok, Google, AppLovin, ironSource, and other ad networks. teams know exactly what "this campaign drove this install" means.

Limitations of last-click

1. 01Ignores upstream touchpoints — the TikTok ad that created awareness gets no credit even though it materially contributed.
2. 02Over-rewards retargeting — campaigns that close already-aware users grab credit from broader-funnel campaigns that created the awareness.
3. 03Doesn't capture brand-driven effects — brand campaigns building general consideration aren't measurable through last-click.
4. 04Distorts channel allocation — over time, budget shifts to last-click-winning channels (retargeting, brand search) at the expense of upstream channels (broad reach, brand video).

When to look beyond last-click

• Multi-touch attribution (MTA)GlossaryMulti-Touch Attribution (MTA)An attribution model that distributes install credit across multiple touchpoints in the user journey — not just the last click. distributes credit across multiple touchpoints. Useful for understanding the full user journey, but harder post-ATTGlossaryApp Tracking Transparency (ATT)Apple's iOS 14.5+ framework requiring apps to display a system prompt and obtain user consent before accessing the IDFA or tracking the user across other apps and we....
• Incrementality testingGlossaryIncrementalityThe causal lift a campaign produces — installs / conversions that happened BECAUSE of the campaign, not just installs the campaign happened to be present for. Measur... measures actual causal lift via holdout experiments. The most rigorous answer to "did this campaign actually drive incremental installs?".
• Marketing Mix Modeling (MMM)GlossaryMarketing Mix Modeling (MMM)A statistical method that estimates how each marketing channel contributes to overall installs / revenue, using aggregated data — no user-level identifiers required. uses aggregated time-series data to estimate channel-level contribution without user-level identifiers.

Mature mobile UA programs run all of these in parallel — last-click as operational source of truth, MTA / incrementality / MMM for big strategic decisions and broader-funnel measurement.