Android 2.2 Froyo SDK Emulator Ported & Running On A Nexus One [Not For The Faint Of Heart, But Here Is How You Can Run Android 2.2 Froyo On A Nexus One Today]
Google has recently announced Android 2.2 Froyo and as of now its not yet available for public consumption. Still, despite not having an official ROM available, some slightly more hardcore Android users have taken the available SDK and created an Android 2.2 port for the Nexus One.

In short, yes you can run Android 2.2 on your Nexus One as of today, but as was described along with the how-to directions, “it’s a real PITA to do,” and “there’s potential to really hose things up.” Honestly I could not have said it any better myself. And while I would not try this myself, I find it fascinating that others are willing.
Given that, if you happen to have a Nexus One, or possibly better yet, a spare Nexus One and some spare time that you can waste you will be in luck. Well, in luck if you are brave enough to give this a shot.

First things first though, be warned. According to the post over on Android Central;
“It crashes (a lot), not much works,”
And without further adieu for those willing to go forward;
1. Download this zip file
2. Place both images in your SDK/tools folderMAKE SURE YOU BACK UP YOUR EXISTING SYSTEM!
3. Boot your N1 to fastboot mode
4. At the terminal or command prompt:
- fastboot flash boot froyo_emu_boot.img
- fastboot flash system froyo_system_emu.img
- fastboot reboot
Finally, and this should go without saying, but if for some reason you do not consider yourself skilled and/or you do not understand the above directions then you may want to think twice (or three times) about moving forward. After all, you could potentially turn your $529 Nexus One into a really fancy looking brick. And that would not be good for anyone, especially the person who has only one phone that they rely on for communication.
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