This only work in KitKat and via ADB only. This does not work below Kitkat.
To start recording your device’s screen, run the following command:
adb shell screenrecord /sdcard/example.mp4, This command will start recording your device’s screen using the default settings and save the resulting video to a file at /sdcard/example.mp4 file on your device.
When you’re done recording, press Ctrl+C in the Command Prompt window to stop the screen recording. You can then find the screen recording file at the location you specified. Note that the screen recording is saved to your device’s internal storage, not to your computer.
The default settings are to use your device’s standard screen resolution, encode the video at a bitrate of 4Mbps, and set the maximum screen recording time to 180 seconds. For more information about the command-line options you can use, run the following command:
adb shell screenrecord --help, This works without rooting the device. Hope this helps.