Measure height using the angle

[Robert321245]

It would be amazing if this app could measure the height of something using the angle.
There are apps that do this but none of them are open-source.

This could work just like a mechanic clinometer:
https://www.youtube.com/watch?v=zjuiKhbZPMs
https://www.youtube.com/watch?v=EahhlAazK1Y