The size of the iPad screen is a bonus when playing on iGraal, but I still think that after comparing the iPad and the iPod gameplay side by side that the iPod is definately more suited for iGraal gameplay more than the iPad is. The buttons are the correct size and in the correct positions so you can simple hit them with your thumb. Then iPad is far too big for moving around too much and the big ass screen just gets in the way. That's my opinion though.
iPad 2 Gameplay
iPod 4G Gameplay