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Comment by pavlov | Hacker News Reader

One of the big differences is that iOS devices have hardware accelerated graphics. You don't really notice how weak transitions and animations are on Android until you get used to using an iPhone. It's a subtle difference, but it's real and it makes a difference.

It's weird that Android still doesn't have this. Even tired old Symbian is now using GPU acceleration for display compositing...

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This is something that is actually pretty tricky. The GPUs on many devices don't allow multiple OpenGL contexts to be created. So in the case of Android, the animations are done in software and the currently running application can create an OpenGL context. This generally makes for slow animations (and unfortunately worse battery life).

What can be done is that the system can create an OpenGL context, and then proxy all other calls (from other apps) through that context with a minor performance hit. This is something that the original iPhone had actually done. However, I think this might be somewhat challenging when working with different mobile GPUs and their quirks.

So while on the surface it's a very simple problem, in practice it can be very hard.

There's a bug in the tracker but it's been shut down for now. The google rep's answer was "This is something we've investigated a couple of years ago already and that we revisit regularly. Of course we thought of using the GPU, but there are non-trivial issues on many Android devices (a G1-class device for instance supports only one OpenGL context at a time, which would prevent you from using any OpenGL based app like games or augmented reality apps.) In our past experiments we even found many cases in which using the GPU was slower than normal rendering. New devices might allow us to overcome the past limitations that made GPU support a not-so-good solution. The "choppiness" and "lagginess" you are mentioning are more often related to heavy garbage collection than drawing performance"

http://code.google.com/p/android/issues/detail?id=6914

No phone left behind?

This is (another area) where Apple's strictly controlled hardware platform fully specified and understood trumps Android's carrier friendliness. Because we consumers aren't the market for mobile phones, however, I don't expect iOS to "win" -- to maintain current marketshare. I also expect Apple to be seriously challenged in terms of user experience by WP7, but never by Android.

DISCLAIMER: Former Apple engineer, reasonably unreasonable fanboy.

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