What does that mean, "All the Bravest?" Well, it pretty much does what it says on the tin. This game is all-combat, all-the-time, with you controlling ten or more characters - I think I count twenty in one of the screenshots - at once by tapping them when their ATB gauge is full. The combat will progress through "stages" in which you battle various monsters followed by a boss. It looks to be pretty low-strategy, as well. There's no indication that you pick attacks per character (which, admittedly, would get pretty frustrating, pretty fast with that many folks in the battle party), merely that you tap them when they're ready and tap multiple characters in succession to create attack chains. The base set of characters appear to be generics, with jobs culled from the history of the Final Fantasy series. There are twenty of these, some of which are unlockable through play.
I think this game has a few things against it, personally. First, with most of the sprites being recycled from other games, odds are there's going to be no coherent art direction in the battles, and it's going to look like a third-grader's collage project - I mean, just look at the title screen. Second, and this won't surprise anyone, but much of the content, including 35 premium characters, are available via in-app purchase, and not for the initial buy, which is expected to be about three US dollars. Finally, if there's really not much more to it than "tap things when you're prompted," it seems like this is a mashup of Theatrhythm and Airborne Brigade, two other recent iOS offerings from Squenix, which doesn't seem terribly innovative when you think about it.
The game's out in New Zealand now, given the magic of world time. Since New Zealand has about nine people, none of whom I know to be CoN members, we might have to wait a little bit to see if my first impressions are indeed accurate.
Sources: Kotaku, Official All the Bravest Site