1. "Android tablet or smartphone is going to be your best bet.....(EDIT)" In response to In response to 0 Fri Jun-05-15 10:23 AM by FLUIDJ
And from there you'll likely need to plan on streaming your music from an outside source unless you get a tablet that's capable of holding an SD card. Samsung tablets do.
If you get an OTG cable you can just plug a high capacity thumb drive into it and have a whole grip of capacity...BUT you can't charge it while that's plugged in...