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Hardware accelerated drawing is not a magical silver bullet to butter-smooth UI. There are many different efforts that have been going on towards this, such as improved scheduling of foreground vs. background threads in 1.6, rewriting the input system in 2.3, strict mode, concurrent garbage collection, loaders, etc. If you want to achieve 60fps, you have 20 milliseconds to handle each frame. This is not a lot of time. Just touching the flash storage system in the thread that is running the UI can in some cases introduce a delay that puts you out of that timing window, especially if you are writing to storage.
• A recent example of the kinds of interesting things that impact UI smoothness: we noticed that ICS on Nexus S was actually less smooth when scrolling through lists than it was on Gingerbread. It turned out that the reason for this was due to subtle changes in timing, so that sometimes in ICS as the app was retrieving touch events and drawing the screen, it would go to get the next event slightly before it was ready, causing it to visibly miss a frame while tracking the finger even though it was drawing the screen at a solid 60fps. (Edit: for those who need this made clear, yes of course this particular issue is fixed.)
• When people have historically compared web browser scrolling between Android and iOS, most of the differences they are seeing are not due to hardware accelerated drawing.
Originally Android went a different route for its web page rendering and made different compromises: the web page is turned in to a display list, which is continually rendered to the screen, instead of using tiles. This has the benefit that scrolling and zooming never have artifacts of tiles that haven’t yet been drawn. Its downside is that as the graphics on the web page get more complicated to draw the frame rate goes down. As of Android 3.0, the browser now uses tiles, so it can maintain a consistent frame rate as you scroll or zoom, with the negative of having artifacts when newly needed tiles can’t be rendered quickly enough. The tiles themselves are rendered in software, which I believe is the case for iOS as well. (And this tile-based approach could be used prior to 3.0 without hardware accelerated drawing; as mentioned previously, the Nexus S CPU can easily draw the tiles to the window at 60fps.)
Und folgende Kommentare sprechen Bände:
Joseph Lee:
Tankut Erinc The irony is Dianne is from the Amiga scene ... If they only treated UI like a video player: it cannot drop frames, and it has to respond.
After playing with NativeActivity and seeing ALooper_pollAll v ALooper_pollOnce, that latency maybe be entirely framework due to poor ideological choice between the two ideas.
21.03.2012 (bearbeitet) +1
Prakash Nadar -
Good information, but with this info, the UI performance of the Android device still remains the same and there is nothing much I can do more to improve it.
https://plus.google.com/105051985738280261832/posts/2FXDCz8x93s
Das Ladegerät ist wirklich mangelhaft im Vergleich zur Leistung. Da sollte Apple ein neues, Leistungsstärkeres anbieten und dieses iPad3 Kunden kostenlos tauschen 
