I bought my navigation unit for, well, navigation. I do love my ipod connectivty, SD cards (saves me burning 100's of CD's per year since I am a music producer) etc. A lot of people hack my unit and do crazy stuff but I have yet to use my DVD player, outside of just testing it out. The main thing I love is all my outputs for my amps, a backup camera that functions while in reverse and the simplicity. I feel like a tablet offers the same in dash as in your hands, it would have to be programed really well to work as I would want while driving. Not trying to be a downer and my navi isn't the best unit in the world but it sounds excellent, better than an expensive Alpine I had before, and has only what I need. If it had more, I would pull over and use it as it was for, much like a tablet or I phone.