During the Facebook Q4 earnings call earlier this week, Mark Zuckerberg hinted that Graph Search for mobile devices is in development, though he wouldn't go into specifics about when it would launch. "Pretty soon," he said, "I think you should expect us to roll out the mobile version of this." It turns out the company is already in the process of testing the functionality, and some users are already seeing the changes.

Mashable reporter Seth Fiegerman noticed the change earlier today and posted a screenshot on Twitter:

Judging from the image, users may soon be able to conduct the same searches for people, places, and timeframes on their phones as they're able to do on the desktop. A Facebook representative later confirmed with The Verge that the company has indeed started a small test of the navigation for mobile Graph Search. The move jibes well with Facebook's ambitions — the company already plans to release a whole suite of apps for smartphones in 2014. Graph Search, with its potential to become a powerful mobile search product, may well become a major part of that rollout.