Co-founder of voice assistant feature Siri leaves Apple

Co-founder of the impressive iPhone 4S voice control feature Siri, Dag Kittlaus, has left Apple.

Kittlaus is someone who’s likely to go down in Apple’s history as having made a big impact on the company and its products. Siri is easily the most recognizable addition to Apple’s latest iPhone. The feature allows users to ask the phone questions, alter personal calendars and even search for nearby restaurants — it’s basically a personal voice assistant you can carry around in your pocket.

Kittlaus’ departure, which happened shortly after Apple launched the iPhone 4S, was amicable and had been planned for a while, reports All Things Digital citing unnamed sources familiar with the situation. The report indicates that Kittlaus wanted to be closer to his family in Chicago and take some time off to work on new projects.

The Norwegian-born Kittlaus was CEO of Siri since 2007, and led the voice recognition efforts of the Siri technology for Apple since Apple acquired the company in 2010. Previously, he was an Entrepreneur in Residence at the Stanford Research Institute and a former Motorola employee.

While Kittlaus has departed, other key executives from Siri are expected to stay at Apple, according to the All Things Digital report.