Watch Tuner is a mechanical and automatic watch testing application designed to measure following parameters:
- rate
- beat error
- amplitude
- beats per hour
The application uses the build-in or headset microphone to record audible ticks of the watch.

You can measure now with your iPhone the quality and stability of the rate accuracy, amplitude and beat error of mechanical watch movements. You can also take advantage of results history.

Use in a quiet environment. Any ambient noises can affect result accuracy. Complete silence is the best.

Recommended way to record the ticks is to touch the crown of the watch with the headset microphone. You will get the best results using original Apple EarPods.

If you don't need such advanced tool as Watch Tuner and all you need is to the check rate accuracy, maybe it's worth to try Watch Tuner Lite - a little brother of Watch Tuner application.
If you need frequency diagram look at Watch Tuner Timegrapher - the most sophisticated app of Watch Tuner series.