Google started to roll out updates for Nexus 5 ,Nexus 4 , and Nexus 7 LTE , users of these devices could check for updates and get it done via OTA. This update mainly focused to improve the camera performance with new feature called HDR+ . This feature provides burst of shots taken in 1/3 of a second which will be useful if you’re in a challenging environment to snap a photo.
Google also claims that this update improves the focus to be faster, especially in low light , better white balancing, with pinch-zoom the viewfinder feature in HDR+ mode and less shutter lag, although the lag is not highly noticeable. For more info on how to get this update manually instead of OTA , head over to Android Central .
Update : This update fixed the problem of exchange server for corporate email as many users faced this problem with 4.4 KitKat. Problem solved!

Nexus 
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