How can I type in the Vietnamese language on an Android tablet?
Unfortunately, the developer of this product didn't released a version that can be used on any Android device.
To type in Vietnamese language on your Android tablet, you can use an application that is developed for this job. An application like this is Vietnamese for GO Keyboard. You can also take a look at Laban Key: Vietnamese keyboard. Both of the suggested applications are free and compatible with most of the Android devices.