One VM per app would need a lot of RAM. Maybe one VM for Linux/Android, and one for iOS, would be a decent compromise. We'd still 'waste' some RAM, but isolation between different Android apps could be handled by cgroups/namespaces.

He said Android or iOS. It seems like massive overkill to have a phone that can run both. Even running Android apps well is a pretty tall order, running iOS apps natively on your own open source phone seems like a pipedream. It took even Google a long time and a lot of investment to get Android apps to work reasonably well on ChromeOS.

If you're talking FreeBSD you would use jails instead which eliminate a lot of the doubled up resources. It's a lot more like docker containers.

True. The question is whether the Linux emulation can be good enough to satisfy Android. There are lots of funny quirks ...

I wish something like CloudAPI/Capsicum would take off to be more secure, while also being an open platform, instead of Linux ubiquity rendering standards irrelevant.

Technically iOS is the closest thing to a *BSD-powered phone, because of the Darwin lineage.

BUt in practical terms it's the most locked platform in existence, so stretching definitions hardly matter here.