The first letter is the code name of the release family, e.g. F is Froyo. The second letter is a branch code that allows Google to identify the exact code branch that the build was made from, and R is by convention the primary release branch. The next letter and two digits are a date code.
Read moreWhat is my phone build number?
1 Go to “Settings”, then tap “About device” or “About phone”. 2 Scroll down, then tap “Build number” seven times . Depending on your device and operating system, you may need to tap “Software information”, then tap “Build number” seven times.
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