First native iPhone apps are compiled. Second Apple specifically made it that garbage collector is not used, although they released it for Mac OS X (Objective C 2.0 runtime).
Here is how low-level - "C", and assembly - for example you can use (depending on the ARM version) various math libraries on the iPhone to get speedup.
Check the oolong engine for more details.
If that's the case - what kind of compiler we are talking here? A really good optimizing compiler would probably use a lot of memory, and cpu clocks.
I'm not expert, so I might be totally wrong about it. Just thinking out loud.
"The Android reference implementation does not (yet) contain such a JIT compiler, though other implementations may choose to provide one."
I thought that was one of the complaints about Android/Java - the VM runs the code; there's no JIT. That's why the prototype Dalvik JIT that was announced very recently was big news. It certainly wasn't announced in the 90s, anyway.