Pinion angle and drivetrain vibration

I know someone already posted on here about the app from Tremec that is used to check driveline angles. It gives you step by step directions. The first measurement is at the back of the engine or bell housing the second measurement is the driveshaft angle and the third is the pinion angle with those measurements it will give you which angle is wrong and how much needs to be changed.
The app is a free download to your smart phone. It works great and has several other features that could be help full. Good Luck on finding your vibration hopefully this is some help