After months of speculation following the launch of D&D 5e and the cessation of the digital versions of Dragon and Dungeon magazines as part of the D&D Insider program in 4th edition, the new version of Dragon has seemingly emerged: on the iOS app store.
As an RPG music soundboard and dice roller for the iPhone/iPad, DMDJ from Blueface offers great “at your fingertips” control in a convenient and portable package, surmounting some of the difficulties of setting up sound in your game, though there remain issues to address.
Dungeon Mapp (iTunes link) fills in a missing piece of that equation for those who play RPGs on a grid, most notably the past few editions of Dungeons & Dragons and its spinoffs. Dungeon Mapp is an app for the iPad that lets a DM build dungeon maps (or wilderness, or several other terrain types), as well as populating the maps with extra features. You can then use it to entirely run your combats from within the app, placing party members, monsters, and managing initiative all from within the program.