Ultrasound Detector APP
On Low activity, there is no ultrasound activity. On High activity, there is some kind of ultrasound activity, and is probably used to provide you better user experience. On Medium activity, you can be sure that there is ultrasound, but it is not sure for which purpose it is been used for - it may be an ultrasound communication or just some maintenance-signal for the mechanic to check a loudspeaker's health.
The central motivation of this work is to give users the control in what their device is up to using the increasingly popular communication medium: Ultrasound data communication. By doing this, we give users the transparency in using Koopango-powered ultrasound features in their apps.
Additionally, we also provide users the ability to check the microphone permission of their installed apps, so that they can see which apps might be able to communicate with ultrasound. If you are in doubt, please contact the apps' developers and ask them. Most of us are nice people, who will reply to you an explanation.