The application you suggested should work 95%. You just have to get your RasPi up and running with OpenELEC(which is a version of the XBMC media center optimized for the Raspberry Pi) and install this app on your Android device and you should be good to go. Otherwise:
- Bluetooth can be a good communication protocol. However, VERY short-range.
- Hello, we have the Internet of Things now! Simply use Eclipse IoT and get up and running with Internet communication to your Raspberry Pi. That's what the Raspberry Pi is meant for- Internet-connected projects! And with Eclipse IoT, you don't need to understand a thing about communication protocols. ModBus, etc are all handled for you!
- As a modification of the previous method, you could use Flask, which is a micro framework for crating a basic server in Python. You can crate a server and access it through practically any device. There, you can provide all the controls you need.
Finally, to all those people who don't try to help from the information given to you, please try to help using the information the guy has given you! I know that feeling, when I need to complete and urgent project, and nobody bothers to answer my question cause they think I need to give the "complete information". Give the guy some help!