App previews can help when motion is the product: games, editors, fitness, drawing, camera, music, and education apps. For simple utilities, a weak video can hurt clarity. Start with the specs before storyboarding.
The specs Apple currently lists
- Length: 15 to 30 seconds.
- Maximum file size: 500 MB.
- Maximum frame rate: 30 fps.
- Formats: H.264 or ProRes 422 HQ.
- Extensions: .mov, .m4v, or .mp4 for H.264; .mov for ProRes.
- Audio: stereo, with AAC accepted for both formats.
Three per language and device size
Apple lets you upload up to three app previews per supported device size and language. The first preview appears before screenshots, so it needs to communicate the app without relying on sound.
Localization workflow
For most indie apps, localize the captions and record the in-app flow in the target language for your top markets only. Voiceover is rarely the first thing to localize because many visitors watch muted.
Source notes
The technical limits above come from Apple's current App Store Connect app preview specifications and upload help.