A full version app for Android, by Haathi Software LLC.

This app is designed to bring you the best possible sound quality to practice or perform with your Tanpura (drone instrument). It includes recordings from a real acoustic Tanpura, tuned to the individual notes. It is designed for both Android phones and tablets and can be used for learning, performing, and practicing music. It is also designed to bring you high-quality stereo recordings and a professional studio environment.

The best thing about this app is that it works in the background, so you can do other things while listening to the recordings.