Siri's top dog jumps ship at Apple -

Just after the iPhone 4S went on sale, which is rather a lot like an iPhone but with improved innards, the co-founder of its flagship feature has left Apple.

AllThingsDigital reports that Siri co-founder, Dag Kittlaus, has moved on. Siri is a voice-activated way to control your phone and was bought by Apple in 2010. 

Since launching on the 4S, it has left some of even the most Apple faithful curious about its usefulness. Certainly, it's a goldmine for pranksters: while the iPhone 4S has resembled hot cakes in its sales records, Macworld recently learned about a security hole which means anyone can use Siri to send messages, even on a locked iPhone.

Of course, AllThingsD reports, Kittlaus leaving the company has nothing to do with the underwhelming nature of Siri as a flagship feature. Instead, it was an amicable departure that had "been planned for a while," according to AllThingsD's sources.

He left right after the 4S was launched. Now Kittlaus plans to look to new business and other entrepreneurial sort of things. 

Apparently other executives of the Siri team will be staying on board with Apple.