Microsoft supports a number of resolutions for Windows Phone 8:
I advice you to take a similar approach as you would with Android. This because Android uses a much wider variety of resolutions than Apple. These variety of resolutions leads to a (more) fluid design where elements don't have fixed widths of heights. This approach also makes your app future prove: who knows what resolutions Microsoft is going to support in the future.
Apple actually has more resolutions for the iPhone since iPhone5 (1136 x 640). The 640x960 is the retina version of the 320x480. The higher resolution displays everything a lot sharper but is not really handled as a different resolution the way you're used to.