Really liking it so far. They've gotten rid of a lot of the BS I can't stand in the main SMT series (main character death, easier to understand demon fusion, ability to map skills to fusion monsters, health recovery at the barracks, etc.) and they've embraced the mobile platform in the best possible way. Gotta love the ability to save everywhere, though it kinda defeats the purpose of the death mechanics if you can just save every ten feet.
Only have two real gripes so far:
The quest system is kinda messed up. It won't let you leave areas if you've accepted a challenge quest even when if the quest doesn't pertain to that area. Ended up thinking I was locked into an area and got really pissed off until I realized it was because I had a quest active. Really not sure what's going on here.
I love that the enemies are visible on screen, but, man, I can't stand the camera. Having them spawn behind you and trying to reorient yourself to attack is obnoxious, and I especially hate it when you get into a battle just as the screen comes in from black on a new area. Huge pain in the ass to have two critical hits to start a battle and nearly dying on level three enemies with a level twelve party. Still, there's less of that Hama Mudo crap going on, so I can't complain too much about that.
Also, anybody else noticing that your party tends to miss more when you select autobattle? That's gotten me killed twice so far, so I'm not even bothering with it again.