Well if it was only as simple as some who have posted suggest. It is not! First, it is not as easy as sending bit to a dac and all the "quality" happens there.
Did you know, for example, that the Android framework will take whatever sample rate files you feed it, let's say redbook and upsample to 48khz? And did you know it will downsample a 96khz file to 48khz. That is for all the players I know of for Android except one, UAPP. And that is before it even gets to the dac......................
And when you move over to the IOS platform you face a slightly different scenario. The stock Apple player will not play back anything above 48khz (at least ios 7 on my ipod 5). Other players will.
So you need to ask yourself, what type files will I be playing back and then decide on some software candidates for each platform. They do sound a bit different even when playing a 44khz file with good headphones. Not that the differences are big, but they are audible to an educated listener.
My experience has led me from the ipod 5 to an Android platform for casual outdoor listening. But it is still nowhere near as good as a properly vetted computer based setup used in the house. YMMV