I have been wondering what the actual build number of Froyo (Android 2.2) on Nexus One was. It is the FRF number that you can read under “About phone” in Settings.

It’s FRF91.

Not FRF83, and not FRF85.

It arrived this morning (Sunday 4 July) on the Nexus One in the UK. So, if you haven’t got that build yet, it is coming soon!