In-app vs mobile web inventory: the quality gap nobody quantifies

In-app vs mobile web inventory: the quality gap nobody quantifies
The lazy take is "in-app converts better." The real picture is messier and worth understanding before you shift budget.

In-app
✓ Stable device IDs (where consented), better viewability, full-screen formats
✓ SDK-level viewability beats web's tab-switching guesswork
✗ SKAN/privacy fog on iOS, SDK fraud (click injection, SDK spoofing)

Mobile web
✓ Easier cross-context attribution, no SDK to spoof
✓ Cheaper inventory, fewer middlemen
✗ Rampant MFA sites, viewability often sub-50%, cookie loss

The nuance: in-app fraud is more sophisticated but lower volume; web fraud is cruder but higher volume. Your detection stack needs different tools for each.

Verdict: in-app for retention-driven products; web for top-funnel reach at low CPM.
Best for: media buyers splitting budget across environments.