Williamson was let go from Apple in November, after Maps was launched to huge criticism from day one. He was replaced by Eddie Cue.
The Maps app didn't have transit directions, it mislabeled locations, and was generally buggy. The outcry from users was so loud, that Tim Cook was forced to apologize on Apple's website. (The apology is still up.)
Before the Maps flap, Williamson had worked at Apple for more than a decade as one of the engineers assigned by Apple co-founder Steve Jobs to build software for the iPhone. He wasn't the only Apple executive to lose his job over Apple Maps. Scott Forstall, who had been running iOS, was also let go, presumably because he refused to sign his name to the apology letter.
Williamson has been at Facebook for a couple of weeks as a manager within Facebook's growing mobile-software group, Satariano reports, citing unnamed sources.
Williamson's LinkedIn profile offers one clue to verify the report. While it still says he works for Apple, there's an endorsement from Scott Goodson, iOS Tech Lead at Facebook, who used to report to him at Apple.
Faceook has hired several other Apple employees, too.
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