Handheld gopro servo gimbal

As I was interested in a gimbal / stabilizer for my gopro, I looked for a way to make one with some small (SG90) servo's. I took the arms of the 'arduino gimbal micro servo'
by Fredrik_JBE (thanks Fredrik, nice job!!) and made the rest myself.
Electronics: Arduino Pro mini and usb interface, GY-521 accelero, 2x SG90 servo's
The .ino files are used for 1. check if the GY-521 is at the right address, 2. calibrate the GY-521 and 3. the gimbal movement itself. Use the values found with the cali