My Nexus 4 is now updated to Android lollipop 5.1 with build number LMY47D.
The L, I understand signifies Lollipop. but how does the rest come into picture
This is an interesting question, but no great mystery as a quick web search leads to the official word at https://source.android.com/source/build-numbers.html
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. The letter counts quarters, with A being Q1 2009. Therefore, F is Q2 2010. The two digits count days within the quarter, so F85 is June 24 2010.
Finally, the last letter identifies individual versions related to the same date code, sequentially starting with A; A is actually implicit and usually omitted for brevity.
Answer:
Yes they are unique Identifier for each version Update.
detail info can be found here on developer.android.com
hope this clears out all the queries.
https://source.android.com/source/build-numbers.html
cheers!
Tags: androidandroid