I tried it with game controler+smartphone. On android, the storage is a mess. No removable SD card either so you're pretty limited actually. Oh and android is clearly not a functionnal OS at all. Works for phone call and that's it.
I use the Sony Xperia Play these Days.
Yes its slow,Yes it have not much Ram...
...but i managed Whatsapp,Telegram,SMS,Phone Calls and GBC/PSX Emulator on it with Android KitKat
It fit wonderfully in my Pocket,Slim Android 4.4 work fine,I can Messaging with it and everytime Play a Game.
I played Final Fantasy 8 complete on this Device and now i am on Final Fantasy IX on Disc3