Unlike other instant messaging programs, ICQ identifies users by a unique number, which today seems a little old fashioned.
The ICQ client hasn't been that sophisticated in the past, but with version 5 it looks as if things are set to change. It comes with what ICQ has dubbed 'Xtraz', which includes such features as sending greetings cards, multi-chats, group messages and much more.
Also included is 'push-to-talk' technology, which you may have seen on the latest mobile phones. Basically, it's walkie-talkie-style communication whereby you can initiate a two-way voice conversation. This is available only if both users have version 5 or higher of ICQ.
ICQ Video has also been improved, with the video and chat window now integrated as one and the ability to take snapshots from a video window at any time.
Note that this is the iOS version of ICQ.