Speaking to Industry Gamers, the studio exec predicted that mobile handsets may become more powerful than current generation gaming systems within the next two years.
"It's amazing to think that when we started Rage, iOS didn't exist. There was no iPhone," he said. "All of that has happened just in the space of one project development timeline. And that's a little scary when you think about it, because major landscape change could be happening underneath our feet as we work on these large-scale projects.
"The fact that it's gotten that close that fast - that means that almost certainly, two years from now, there will be mobile devices more powerful than what we're doing all these fabulous games on right now."
Carmack went on to say that the phenomenal popularity of casual mobile games like Angry Birds will not impact on blockbuster console releases.
"Could the bottom drop out on the triple A market because everyone's playing Angry Birds? It doesn't seem to be happening.
"The numbers don't show that. We're selling more big titles than ever before, despite having all of these other platforms out there. So it looks like it's parallel growth rather than one stealing from the other."
Rage is due for release on Xbox 360, PC and PS3 in October.
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