While there aren"t any details at this point, Injustice series director and NetherRealm Studios head Ed Boon announced via his Twitter that there would be a mobile version of Injustice 2.
Similar to the first title, Injustice: Gods Among Us, the studio will most likely release the game for Android and iOS. While some may scoff at the idea of a mobile version, the release was a fairly robust title that boasted excellent graphics, gameplay, and depth. Boon stated that the next iteration will include new features, modes, and combat system.
The studio is quickly ramping up the title before its May release, trickling out new tidbits about its roster on a weekly basis. More recently, it was announced that Swamp Thing would be making an appearance in the game as a playable character. They also recently had a beta for the game to test out the online portion and its stability. Injustice 2 will arrive on the Xbox One and PlayStation 4 on May 16 and can currently be pre-ordered online or through your local game retailer.
Source: Ed Boon (Twitter)