I would like to create a tilt control schematics for my marble rolling game, similar to Gears, or Mad o Ball 3D.

I would like to ask for some advice, example, or guide on how to create a system like this. I know I have to use Input.acceleration, but some things are not clear. Like how to handle the calibration, or how to check for the device's angle, to set a maximum angle of acceleration.

Thanks for your help!