[tolmasky]

There are certainly classes of mobile apps that need the guarantees of lower/deterministic memory usage. In my experience, that is not the common app being written however. These concerns seem largely like fantasies not backed up by any concrete evidence for your every-day twitter client/mail app/weather/whatever. Generic list-based apps simply do not need to be acting as if you need to squeeze every ounce out of the processor/ram anymore. They would instead benefit much more from not having to worry about whether self in the closure you're creating should be weak or not. Especially when you consider that many (most?) of the apps on the App Store that are actually pushing things to the limit -- games -- are running in a (old) GC environment (C# in Unity).

[mnem]

I would be quite surprised if most App Store games were created with Unity - it's expensive and (comparatively) cumbersome to develop in, especially if you're just using 2D graphics (even with the fancy new Unity2D stuff). I can't find any stats on mobile game engine use though, which is a shame because I think it would be interesting to know.

When creating Unity3D games, you have to be reasonably careful about garbage collection - lots of nasty performance dips result if you assume that it just works. Generally you have to cobble together a mixture of object pools and statements attempting to force collection at a convenient point in the game flow amongst other things. It would be quite nice if you could turn it off for specific portions of code :)

[mnem]

Found some interesting statistics on this site: http://www.iresearchchina.com/views/5604.html

I suspect to get anything more detailed you may have to purchase a paid report from one of the various analytics companies.

Sorry, I've wandered rather off topic...

[bad_user]

Unity uses an older Mono (2.10 I believe) which has a poor GC that's not even deterministic, so you can easily suffer memory leaks. It is also not generational. Newer versions of Mono come with a much better GC.