Android compatibility is a problem... Because they don't have control over every piece of hardware, application developers have trouble getting their applications to work across platforms. Go look at any number of apps in the "play" store, and you'll see comments "doesn't work with phone X or phone Y, glitchy with phone Z, freezes constantly on phone A and B" Most applications are pretty universal, but there are exceptions to many... if you go to the apple store, you'll find MUCH MUCH less of those types of comments, if ti works on iphone 4 it works on iphone 5 and so on.