I'm not sure why these devices are coming out, trying to turn casual phone games into AAA experiences. Even when the big companies are on board making games for this market, they are watered down experiences. For example, there was a new Rayman game made for mobile that is really fun, but all you do is run through the levels collecting things. Basically it's a shallow game that would never convince anyone to pay $60 at retail.
Really, when I want to play those types of games, it's when I got 10-15 minutes to burn somewhere. I'm not going to come home and dive deep into countless hours on these mobile games.