The iDEN system supports half and full-duplex operations. Half-duplex enables only one user to talk or transmit while the user on the other end is listening or receiving. In full-duplex, there is an open bi-directional link allowing both users to talk and listen at the same time. Half-duplex is employed in walkie-talkies, while full-duplex is used in cell phones and telephones.

Just like many of today’s advanced cell phones, iDEN phones can support SMS messages, voice mail, and data networking such as VPNs, the Internet, and intranets. iDEN is not the only PTT service. In the U.S., there is Sprint’s Qchat and Verizon’s PTT. On March 2011, Sprint announced that it is decommissioning its iDEN cell sites, with a full phaseout planned for 2013.

Some of the iDEN phones from Motorola include the Brute i686, the i886, the i1, and the i576.