Google promised at their Nexus 5 & Kitkat 4.4 launch event that Nexus 4, Nexus 7 & Nexus 10 all will receive android 4.4 Kitkat update. The promise has been fulfilled as the official Android 4.4 Kitkat update is now rolling out for all the above mentioned devices. The update is made available through OTA (Over the Air) so check your devices for it if you haven’t done it yet.
About Nexus 7 (2012 and 2013 Wifi models) are the ones receiving this update, the mobile network (4G) will receive an update soon, it might be the optimization for the cellular radio that is getting in its way. Also keep in mind that to accept the OTA as-is, you’ll need to be running the latest stock build from Google, though an unlocked boot loader should pose no problem.
