Anti Mosquito Repellent Sound Simulator is a free app that emits a special high-frequency sound at high frequency that most mosquitoes dislike and will prevent mosquitoes from biting.
There are a lot of mosquito species in the world and some of them may be resistant to ultrasonic sounds which this app is simulating.

Note: This application is not endorsed by science it is developed by developer personal way, you can experiment this app.