I have a K1 and an iPad Pro 9.7...The compass doesn't work on my K1(google it) and the screen glare is bad...I added an anti-glare screen cover and a hood and it still wasn't great...On the iPad Pro everything works and the screen glare is reduced by something like 50% as I think it is for the mini 4 also...I don't even use a hood with it...Comparing the two tablets is like night and day but you do pay for that...If you go with iPad and you want GPS you will need the cellular model...The ONLY thing I miss on the K1 is the HDMI port...It mirrors the screen to my Head Play goggles...Now with the iPad I have to use the HDMI port on the back of the controller and it doesn't mirror the screen exactly.
Check out this video comparing screen glare