I used a bubble level program (just called "Bubble" on Android market) for no more than 15-20 minutes today... Battery use: Bubble: 31% Cell standby: 27% Phone idle: 23% Android system: 13% Display: 6% Now...this is not an often used program, so it's not a big deal. I did notice the battery dropping around 3-5% after 10 minutes of use. I don't know of a faster way to drain the battery. What I am curious about: What would cause a bubble level program to use so much battery? Is the phone's gyroscope (I'm assuming the program uses the gyroscope or accelerometer or whatever HTC puts in their phones) that power hungry??