[Razengan]

> I wish the Google Play Store/Apple App Store did things half as well as Steam does, like: > Backing up application data in the cloud (game saves)

iCloud has been doing that for years, with more features and flexibility for both users as well as developers than Steam.

> Update priorities (ASAP, before next launch, before everything else)

Disable auto-updates and let the user decide. Manually choosing updates works better on the App Store than on Steam.

> Update windows (like when the phone is idle in the middle of the night, not when I'm in the middle of using it)

macOS, iOS, tvOS and watchOS all let you choose whether to download OS updates in the background and when to install them.