Why? Be a bit like watching a divx film on your computer and not full screening it.
I agree if small phone screens were the only option, but with ipads and tablets with 10 inch screens and even larger mobiles would benefit from something to play rather than bloody candy crush whilst say on a tedious train or car journey
Just off top of my head but i am sure any app for fme would be a lot more forgiving in battery drain than most modern apps, that is a bonus