How to find out firmware How does one determine what firmware they are using? I've looked in settings -> about phone and can't find it. I know I'm using Android 5.1.1 and have CM.
It depends and differs by the mobile manufactures. 

For Sony, Samsung and Motorola devices you can find in Settings &gt; About phone &gt; Build Number.

If you have a Samsung device you can also check the version of firmware you currently have by dialing *#1234#.

In HTC devices it will be under Settings &gt; About Device &gt; Software Information &gt; Software Version. (eg. 3.16.401.9)

The firmware number consists of several elements, all of which are essential for the functioning of the phone:

- PDA: Android operating system and your customizations.
- Phone: the actual identifier of your device.
- CSC (Country Exit Code): the languages and country-specific parameters.
- Bootloader: the boot loader program that runs at startup to all unit processes.


 

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