The boat unit is an optional component of the UDI system. It is used for text message communication with the underwater divers, and its Homing capabilities allow divers to navigate their way back to the boat. The UDI boat unit contains the following functions:

• Message sending/receiving
• Homing beacon
• Dive logger
• Electronic compass

The Boat unit supports 4 different networks (groups), of up to 56 divers - with a push of a button.