WindowsMania has managed to get their hands on the official firmware of the Amber update for the Lumia 820 and 920.
The update allows Lumia devices to use the FM radio feature that was dormant till now. It also increases the maximum possible ISO setting when taking still images, from ISO 800 to ISO 3200. The increase in ISO level enables the camera to take in more light in a lesser amount of time.
Another feature that is new with the Lumia Amber is Nokia’s Smart Camera Lens app that gives you the ability to take shots in a bust mode. Utilities like Best Shot, which allows you to pick the best image out of a selection, and Action Shot, which shows a sequence of shots in a single image are added in. Image editing tools like Erase Object and Change Face are also included.
Get the Amber firmware for the Lumia 820 and 920 from the links below. But be careful, unlike OTA updates flashing these ROMs will delete all the data on your device.