i definitely heard it, and i would never use that as a ringtone. if i'm in school then my phone is always in my pocket, so vibrate would be much better. it didn 't sound like a mosquito though, more high pitched and annoying. mosquito's are more of a buzz than this squeal. although my hearing is top notch because up until this spring i had a good buildup of ewax in my ears and my hearing was blocked. i never knew about it until i wdent to the doctor and they do the routine ear check. i though my hearing was normal, with nothing to tell me otherwise. so basically, i've gone years without losing hearing that the average teen and child loses. i had a week long headache after it was fixed and every little sound hurt. so yeah, i'm good for a while.