Strictly speaking, a PC is not required for participants to join a Calliflower conference call. However, if participants wish to be able to access any of the online conference calling features, such as the text chat, recordings or raise / lower hands features, then a PC becomes a necessity, even if only to access recordings after the call.

Calliflower is a web application. It will work on any operating system that is capable of supporting a modern internet browser, such as IE 7, Firefox 2 or 3, or the latest Apple Safari browsers. The only other requirement is that Adobe Flash Player 10 or better be installed.