The Mosquito Ringtone is a high pitch sound that those with young ears (teen agers) can hear but many adults can’t. Your mobile phone may or may not reproduce 17000 Hz sounds so try it before depending on it working.
Download the Mosquito Ringtone for free as an M4R file.
Mosquito Ringtone M4R format
Configure your phone to vibrate when a call or text comes in as well as use the mosquito ringtone. You can feel it; no one else can hear it.
Try the silent ringtone too.