We're not sure how long this has been possible, but at launch, Amazon's Cloud Player refused to stream songs from your Cloud Drive in Mobile Safari, with the only alternative being selecting 'Download' instead of play. Now Amazon has quietly flicked the switch that allows Cloud Player to work properly in Mobile Safari, once you get past the "Your browser isn't supported screen," complete with background playback and control, meaning that you can pause the music and skip tracks right from the multitasking bar.
If you haven't tried Amazon's Cl