Could be improved if the bubble had two """"""""""""""""sensitivity"""""""""""""""" settings. I used a standard 24 inch framing level to find a a completely level place on my concrete floor to calibrate both my phone and the app. This app has the bubble move through 360 degrees of angle  while a framing level only provides meaningful reading for about 2 degrees on either side of the angle  a range of about 5 degrees  so when you are close to level the bubble does not add value with this app  but the readings do. Though on my phone even when sitting on a concrete floor the readings would flicker between a couple of tenths of a degree. I suspect this is a hardware (phone) issue not a software (app) issue. Also the app works without being online  and does not have ads.""
July 11 2015