First method (via ADB):
Procedure (Nexus 7 2013):
1. Download the official Android 4.4.1 update zip file for Nexus 7 to your computer.
2. Reboot your device into recovery mode. Switch off Nexus 7 and reboot it. While it is booting up, press and hold the Volume Down button until you see Recovery and then press the Power button to enter it.
3. Connect your device to your computer via USB.
4. Use the volume keys to highlight “apply update from ADB” and select it using the power button.
6. Now the folder where you downloaded the official Android 4.4.1 update zip file and open a command window (press Shift button, right click mouse and choose open command window here)
7. Now type the following command:
adb sideload b5559302dc8273444cb8234b5a6c22c863441e84.signed-razorg-KOT49E-from-KRT16S.b5559302.zip
The update will now be installed on your Nexus 7. After the installation is complete, reboot your device. You have successfully updated your Nexus 7 to official Android 4.4.1.
Second method (Via Custom Recovery)
If your Nexus 7 is rooted and custom recovery installed, you can update your device to Android 4.4.1 via custom recovery.
1.Copy the downloaded official Android 4.4.1 update zip file to the root of the internal storage of your Nexus 7.
2. Turn off the device and boot into recovery mode.
3. Select “install zip”, then “select zip” and choose the Android 4.4.1 update zip file.
After the installation is complete, reboot your device. You have successfully updated your Nexus 7 to official Android 4.4.1.
