While alternative app stores operate independently and are required by EU law, Apple is still in a position to exert some control. This became apparent a few weeks ago, when iTorrent users suddenly ran into trouble when installing the app.
Thought this was an interesting story, since it’s pretty analagous to the recent Android situation, with third party app stores being enabled to some extent, but the company retaining ultimate censorship power.
How useable is Linux phone compare to Android/iPhone?
It isn’t.
If it’s Sailfish OS (Xperias or Jollaphones, updates are paid), apart from apps (hit or miss if it’s popular enough, pure miss if it isn’t), everything works fine (I guess, I haven’t tried it).
If it’s anything else, it’s still murky.