I don't have a tablet, but I've been looking at a lot of them. iPad seems to be the favored solution for aviation and if you add magazines, quantity & quality of apps and ease of use. If one wants on-board GPS, they have to get the cellphone chip'd version. I'm looking to make this tablet my all-in-one device, but not replacing my mobile phone. An eFB, pseudo-laptop, travel entertainment center & etc. You get the idea. Questions with aviation in mind: 1) Anyone using BadElf (and the like) instead of built-in GPS ? 2) Advantages/disadvantages to add-on GPS units ? 3) How much memory is enough 32GB, 64GB or 128G ? 4) iPad Air future proof enough ?