<b>Rewarded vs interstitial as UA sources: the LTV divergence</b>

<b>Rewarded vs interstitial as UA sources: the LTV divergence</b>
Buying installs from rewarded placements vs interstitials pulls fundamentally different users, and the eCPI hides it.

<b>Rewarded-sourced installs</b>
✓ High intent-to-act, users who finish actions; great for engagement funnels
✗ Incentivized — many install for the reward, not your app; D7 retention often craters

<b>Interstitial-sourced installs</b>
✓ Non-incentivized, closer to organic intent
✗ Higher CPI, lower volume, more accidental clicks (fat-finger on close button)

The metric that decides it: not CPI, not D1, but D7+ retention and event-completion by placement type. Rewarded can look amazing at D1 and worthless by D7.

<b>Verdict:</b> rewarded for cheap volume you'll ruthlessly cohort-filter; interstitial for quality you'll pay up for.
<b>Best for:</b> UA managers tuning source mix by retention, not CPI.