The Android 4.1 Jelly Bean ROMs for the Samsung Galaxy Nexus have been already rolled out, while the HTC One X is going to join the action too.
Based on SDK, the ROM created by an XDA-Developers member is currently based on the Galaxy Nexus images. Still the port has issues with the camera, audio and Wi-Fi.
But agree that it is amazing, how quickly a new Android can be installed in a new smartphone based on a quite different chipset. Watch the video to see Jelly Bean running on the HTC One X.
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