iPad Mini 4 or iPad Mini 2
If I was been honest with you would be better waiting for the new iPad mini coming out after the Apple event it only a couple of weeks a away now until the event the iPad line will be out and some will be new iPhone and maybe so a new Mac line up to
I personally wouldn't bother with the iPad mini 2 or 4 because they are getting old now and it won't be long until the apps won't be working at all and their is nothing you can do with the device at all but sell the device .
I would hold on personally and wait for the new iPad mini line to come out and buy that one and then you you would get your use out of it a least 4 years or so.
I have had two iPad mini and I thought the screen was quite small so I have just bought iPad Pro 9'7inch 32gb versions I am very enjoying using it a lot better for movies and reading and thing I find it a lot better then the mini .
Just remember one the mini roughy only about 4 phones put together not very big to be truthful with you but it might suite your needs for me it didn't for because I watch movies on mine a lot when I am bored or I have a long wait some where and I have nothing to do.
If you have not looked at a iPad Pro 9'7 inch I would take a look and you might change your mind when you see it close up I know for. a fact now that I wouldn't never go back to using one of coarse that is my personal view but we are all different what we like the reason why I am saying this because I have read many of times of forums I wish I bought the other version and they had to sell the version they currently have to get the other version
I hope you are happy with your purchase which ever one you buy