Apple is forcing it's 3rd Party developers to start submitting screenshots in it's 'Retina Display' resolution, which is 960x640.
This likely means that they are dropping support for the iPhone 3GS and other older devices soon.
So, save yourself time and energy by switching your project over to 960x640 resolution immediately, instead of using 480x320.
NEW EDIT (APRIL 2, 2012):
I just wanted to throw this out there about the iPhone and iPad resolutions.
iPhone 3GS and earlier: 480x320 pixels
iPhone 4 and later: 960x640 pixels
iPod Touch 3rd Gen and earlier: 480x320 pixels
iPod Touch 4th Gen and later: 960x640 pixels
iPad 2 and earlier: 1024x768 pixels
iPad 3 and later: 2048x1536 pixels
Having ran my Water app - designed for 480x320pixels - on a Retina Display iPad 3, I have to say that it looked a little blurry, but still relatively decent (I turned min/max filtering to nearest neighbor).
Having ran my Caves of Isna app - designed for 960x640pixels - on a Retina Display iPad 3, it looked clear and sharp, with no graphical degradation (I turned min/max filtering to nearest neighbor).
If targeting all iOS devices:
Develop with 480x320 in mind. The first iPod Touch's and iPhones don't have the processing power and memory to handle high resolution graphics. The app will look a little fuzzy on new devices, but still workable.
If targeting current iOS devices:
Develop with 960x640 in mind. The iPhone 3GS has enough horsepower and memory to handle rendering a scene at 960x640. This resolution will look great on all other devices with and without Retina Display support.
If targeting future iOS devices:
Develop with 1920x1280 in mind. This will scale down perfectly on the iPhone 4 and 4S, iPod Touch 4th gen, and will look great on all iPads. It's not exactly Retina display resolution for the iPad, but it's close enough. It will still look fantastic
Could this become a sticky?
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