How can I calibrate the tilting sensor on Android
It's a tough one to answer, as I'm not sure what version of Android you are running, and you have stated it may be a clone. 

Method 1:

Open "Settings"

Find "Motion" and tap on it

Scroll down the menu and tap on "Sensitivity Setting"

Open "Gyroscope calibration"

Place device on a level surface and tap Calibrate

Method 2:

Download 'G-Sensor' from the Samsung Apps store pre-installed on your device.  Here is a weblink. 

Method 3:

Download  Bubble Level  from the Google Play store, this has a calibration option also.