Related Clues:

• Use a PDA, perhaps
• Thing at the end of the line?
• Cellular transmitter
• It has a familiar ring
• A Christmas connection
• Bell's ringer?
• It transmits speech at a distance
• Transmitter of spoken words
• It converts sounds into signals and back again
• Transmitter of speech, and now text and pictures
• Communicating tool
• Electronic sound equipment
• Has trunks
• This may make someone callus, perhaps
• The ring you get with this would never have 4 across in it