If you didn't know, Android is open source (at least the majority of it)!
Android Open Source Project technical lead Jean-Baptiste Queru has announced the source for the newest version of the OS, Android 4.1 Jelly Bean will be made available today.
Currently, binaries are available for the Nexus 7 and Galaxy Nexus, with Nexus S and Motorola Xoom versions promised soon. This also starts the countdown for OEMs to build their custom tailored updates as well, in addition to the third party coders such as CyanogenMod.
For more info, jump into the source link below.
Source: Android Building Google Group
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