There is a way for you to install almost of Android application by ROOTING your device. By doing it, you voided the warranty from the producer. Actually, you can install new apps without rooting your Kindle. Here is how I do it.
Step 1. Find a suitable APK applition on the Internet
Step 2. Turn on "Allow Installation of Application" (Setting -> Device)
Step 3. Use
OpenSuite Pro to install the apps (
filter it if you can't see your APK file)
Now, you can install any application on your Kindle without rooting your device.
Have fun!
(From Tinh Te)