Last Updated: Apr 05,2010
What does that mean? "-update1" more updates coming or patches?
This is just speculation, but it's because of the Nexus One. 2.1 was obviously first released with the Nexus One but when it came out there were a few bugs that needed fixing. They quickly patched it, but it didn't add any features or change anything so they didn't go with a new version number - hence 2.1-update1
so pretty much like 2.1.1
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