Great piece on why the iPhone has an intrinsic advantage over Android devices by trader, analyst and algorithmic trading expert Paulo Santos. 

"This intrinsic advantage allows Apple to run Apps in its devices faster than those same Apps would run on Android devices with comparable hardware specs; or alternatively, to consume less power when running at the same speed. This is non-trivial for Apple, for both performance and power consumption come at a premium in battery-reliant mobile devices. It's also non-trivial because an architecture decision is something which stays rather immutable over long periods of time, so any advantage gained is hard to overcome."
"...The problem here is that translating code at runtime, or compiling at runtime, can have a serious impact on performance versus just running native code directly. Theoretically the JIT compiler could target the specific hardware the program is running on and produce faster code, but since Apple's compiler also targets a very limited set of hardware, such advantage is nullified. What isn't nullified, though, are the disadvantages introduced by the need to translate or compile at runtime."

Note: Windows Phone 7 ran on a similar structure as Android but Microsoft must have learned the value in native running code and switched to a similar structure as Apple in Windows Phone 8. Probably at least part of the reason for Microsoft's abrupt lack of support for Windows Phone 7. Better to right the ship sooner than later.