How to check the software version on T-mobile LG G3 (LG-D851) :
1. From the Home screen, Long-press Recently used app key.
2. Tap System settings.
3. Tap the General icon to display that tab.
4. Scroll down to ‘SYSTEM,’ and then tap About phone.
5. Tap Software information.
Read the version on the phone, and check it against the one below:
T-mobile LG G3 D851 Software Version: D85110m / Current
T-mobile LG G3 D851 Software Version: D85110C / Initial release
If they match, your software matches that of the initial release. As new firmware is released, you will be able to check to always make sure you’re running the latest version.