Mobile games are mostly shit.
A couple are decent, but man is it hard to find them, especially if you don't have a community like GAF to help.
Yep. There's been a couple I've liked but I mostly found them via GAF, the rest I've tried I usually played for about a day or two and then deleted out of boredom.
Device 6 was amazing but I don't even know if that counts as what you think of with "mobile." Otherwise a vast majority of them are pretty crappy.