Monopoly over iOS or Android is a bit murky definition IMO. They are both creations of those companies and it seems fine for them to have a monopoly over them.

Monopoly over iOS or Android is a bit murky definition IMO. They are both creations of those companies and it seems fine for them to have a monopoly over them. Ring devices by Amazon or Nest devices by Google can have a monopoly over the devices in their ecosystem but no one cares [yet]. Mobile computing is what Apple and Google have created and of course you need to go through them to access the users there. You have to go through MS and Sony for example to access game console users, duh! The issue is if for example tomorrow a new company builds a nicer hardware and software package there's no easy way for users to migrate. The migration cost is super high. That company can't emulate iOS or Windows to be compatible with the existing apps. I don't think they can do a clean room reimplementation of the OS calls either. The users would need to repurchase all the apps, music, games, movies and other media they've already paid for even though none of those content were created by the platform owners. Imagine running a web server on Azure VMs and try to migrate to AWS to GCP but then realize you need to repurchase all the stock images you used in your website and any other software you run on your servers. I think for popular enough platforms like iOS, Android, Windows, etc. the cost of switching should be regulated. That way the quick feedback loop from consumers will ensure the platforms owners are always kept on their toes to keep all the consumers happy without relying on the moat they've built.