Do they offer many services for *OS apps or are they mostly independent and only service their own first party apps?
Theoretically they offer quite a few; in practice, I think nowhere or almost nowhere I've ever worked has gone for those options (except my own self-published games), instead preferring a custom solution that can be shared with web and android.
iCloud is the backend for basically any settings/file sync for normal apps.
Theoretically they offer quite a few; in practice, I think nowhere or almost nowhere I've ever worked has gone for those options (except my own self-published games), instead preferring a custom solution that can be shared with web and android.