Quiet calls

Quiet Calls is a technology allowing mobile telephone users to respond to telephone conversations without talking aloud. QC-Hold, a Quiet Calls prototype, combines three buttons for responding to calls with a PDA/mobile phone unit to silently send pre-recorded audio directly into the phone. This permits a mixed-mode communication where callers in public settings use a quiet means of communication, and other callers experience a voice telephone call. An evaluation of QC-Hold shows that it is easily used and suggests ways in which Quiet Calls offers a new form of communication, extending the choices offered by synchronous phone calling and asynchronous voicemail.