Two of Apple's top executives are leaving the company: Scott Forstall, who has overseen the iOS platform that runs the iPhone and iPad, will leave Apple next year, and John Browett, senior vice president of retail, is leaving sooner, Apple said Monday.

Forstall has played an important role as senior vice president of iOS software and has been a high-profile figure at the company, often sharing the stage with the late CEO Steve Jobs and other executives at mobile product launches. Prior to his departure next year, he will serve as an adviser to CEO Tim Cook.

[Macworld UK edit: iOS VP Scott Forstall was blamed for inadequaces of Apple Maps and Siri, and John Browett joined Apple from UK retail store Dixons earlier this year and shortly after encountered issues when it appeared that a number of retail store employees had been laid off, apparently due to a mistake, they were later reinstated.] 

Craig Federighi, senior vice president of Mac Software Engineering, will now lead both iOS and OS X development. Apple said the change would "make it easier to deliver the best technology and user experience innovations to both platforms."

In retail, the search for a new chief is now under way, Apple said.

Forstall's and Browett's departures were announced as part of a broader reshuffling at the highest levels of Apple management. The company said the changes would encourage more collaboration among its hardware, software and services teams.

In addition to Federighi, three other top executives are taking on more responsibilities.

Design guru Jony Ive will lead human interface design across the whole company while remaining head of industrial design. Eddy Cue, senior vice president of Internet Software and Services, will add responsibility for Apple's Maps and its Siri voice interface system.

Bob Mansfield, the longtime manufacturing chief who announced his retirement in June but decided in August not to retire after all, will lead a new group called Technologies. His group will bring together all of Apple's wireless teams as well as its semiconductor teams. [Macworld UK edit: According to reports, Apple engineers kicked up a fuss about Mansfield's replacement, Dan Riccio, causing Cook to go to Mansfield and ask him to stay]

Stephen Lawson covers mobile, storage and networking technologies for The IDG News Service. Follow Stephen on Twitter at @sdlawsonmedia. Stephen's e-mail address is [email protected]

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