Speaking at QuakeCon, studio co-founder John Carmack admitted that the decision to close id's mobile projects "saddened" him, but the talent being employed to make them were required for Doom 4.

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As the iOS market flourished, Carmack made his enthusiasm for the new market clear, establishing a mobile team in 2007 that has produced six games, largely based on id's classic IP. The studio has "a couple of projects" for mobile on hold, including one that is basically finished, and Carmack made it clear that he intends to return to the space.

"I hope we get back to mobile in various ways in the future," he said, "but the big real aim is blockbuster, AAA titles, and for id that means Doom 4, it means that we get the whole company behind that after we get Doom 3: BFG Edition out the door. Essentially, everybody will be focused on Doom 4 as a project."

However, when asked about the possible release date for Doom 4, Carmack was evasive.

"Every decade there will be a Doom, but hopefully we can do better than that."