Out of interest is there any reason why ipads are separate from tablets and same with ipod and iphone? - they are the same software running the same browser! Merging them could have given you space for more distinct devices (Android/Win Mob)
All iPads are tablets, but not all tablets are iPads.
Since iPads and tablets were shown separately, I assumed the latter meant a non-Apple device. I ticked both because I use an iPad and an Android tablet.