I'm pretty sure the app is just the "Red Box", the introductory 'Beta' version of the game. It's a self-contained, fully playable game that you can spend $5 on and play for ever (or, at least, for ever in five-level bursts). If you're expecting support, do not purchase it - the game itself should be out soon (*ahem*).
It's not going to be updated because it's not an app of the full game, just the Red Box version of the game. Compared to the full game it is smaller, and more primitive. It is the australopithecus afarensis version of Dungeon*World. The current beta is the Neanderthal version, much further along on the evolutionary ladder and much much more robust.... then we'll get the prerelease Cro Magnon, followed by the full-blown, Anatomically Modern release version!
World of Dungeons is a lemur. There is no Gigantopithecus in this metaphor, though if Antisinecurist and I can ever put together this Psionics book it might be bloated and massive enough to be given that name ;)