The SleepApp captures the sound from the mobile telephone, samples it and filters it to identify snores using a "Snore detection algorithm developed by Marc Farssac". There are important things to take into account when doing this: First, every telephone has a different microphone with different electric characteristics and of course, they are not calibrated or adjusted by any means. Second users can place the telephone at more or less distance from them. Third, they can turn left or right while sleeping reducing the noise level recieved by the phone. And also, every snorer is different. Last but not least we have to define what is a snore. Imagine, there are some considerations needed to develop it, still, it works and you can install it from the Google Play store or find out more here