Ipad mini 2, 3 only
ipad air 1
ios 7 if you can find it
ios 8 otherwise
less preferred ios 9
ios 10, i will not buy the above devices with ios 10
ipad air 2, ipad mini 4 and the successors are just different, made more towards pleasing the crowd with better numbers on performance, thinner, better looking colors yada yada whatever to sell it, while sacrificing the picture quality, performance. ipad mini 2, 3, air 1 have just better picture quality, not messed with, not as manipulated,