The present invention in general relates to a voice decibel application and a method for a phone and in particularly relates to the application and the method for a phone to measure the voice decibel during a phone call. The application incorporated into the user's phone is configured to measure the voice decibel during a phone call and send a signal to the user in case the voice decibel exceeds or goes below a preset voice decibel threshold level. The present invention is advantageous because it will help the users to recognize their talking habits and assist them in improving their talking habits.