Amazon's popular Kindle Fire HD 8.9-inch tablet is loaded with a (default) custom fork of Android 4.0 Ice Cream Sandwich (ICS).
However, after many months of coding and tweaking, it is now possible to install an early build of Android 4.2 Jelly Bean on the tablet with CyanogenMod 10.1, courtesy of a developer named Hashcode.
Meaning, users can download apps from Google's expansive Play Store rather than being limited to Amazon's curated app storefront.
Although the Kindle Fire HD tablets are somewhat hobbled by locked bootloaders, you can still install a 2nd-bootloader, facilitating the installation of custom recovery, backing up and wiping your device, as well as installing a custom ROM such as CyanogenMod.
As Liliputing's Brad Linder points out, the process is hardly foolproof at this stage, so caution should be exercised. Indeed, even with Hashcode's detailed step-by-step instructions something could still go wrong, leading to a bricked device.
It should probably also be noted that CyanogenMod 10.1 for the Kindle Fire HD 8.9 is still considered a work in progress, with non-functional audio, crashing camera and half-functioning Bluetooth support. What does work? WiFi, video and hardware accelerated graphics.
Interested? Detailed instructions can be found here (bootloader) http://forum.xda-developers.com/showthread.php?t=2128175 and (Cyanogen Mod) here (http://forum.xda-developers.com/showthread.php?t=21282010) .