A free program for Android, by My Language Apps.
Easy Bangla Keyboard is the best Bangla keyboard for Android. With a new design, you can type in Bangla with ease. The layout is also optimized for quicker typing.
The word prediction is also improved, so you can type without having to look at the keyboard. You can use it with any app, including the most popular ones. You can also set it to work with your favorite app, so you don't have to remember the key combination.
It is designed to be simple and easy to use.