This is a bubble level app that keeps reading the tilt of your smartphone with a synthetic voice.
It is convenient because you can work while listening to the voice read aloud when adjusting the angle of something.
In addition to tilting, it can also read the direction aloud.
You can also adjust the reading interval.
It will not work unless the TTS engine is installed on the smartphone.
Depending on the model and TTS engine, it may take a few seconds for the start button to take effect.
It cannot be used on smartphones that do not have a tilt sensor.