> Since Android/iOS already have sandboxing and per-app permissions, the only benefit to having a single distributor is the potential of having that application

> Since Android/iOS already have sandboxing and per-app permissions, the only benefit to having a single distributor is the potential of having that application scanned for malware... Well, if a malicious app store application existed, I'd imagine it would work via social engineering and sending the user a different package than the user wanted. The user will be convinced to override the sandboxing, e.g. by giving permissions to install a 'new version of WhatApp', but the store app will actually be installing something else with the given permissions. That's a bit easier compared to other apps where the user doesn't expect to install anything. (Perhaps I'm missing a clever way to deal with these possibilities?) I don't think that the risk requires banning 3rd party app stores. In practice we see the risk is very low. I have little worry about F-Droid, and I'm sure that the Samsung/Amazon stores are as secure as Apple/Google. But I think a bit of warning is justified. >True that Steam is kind of questionable when it comes to security, but that's more the fault of the desktop operating systems which don't have sandboxing built-in. Debians/Ubuntus have (optional) AppArmor, and latest Windows 10 Pro+ has an sandbox which will work with Win32 apps. It's starting to become built-in, even if not yet. It'd would still take a lot of work.