CMAR is a platform for collaborative mobile augmented reality, which allows several users to interact and manipulate with a shared scene on consumer mobile phones in real-time. Up to eight users can collaborate in an augmented reality environment trough the Bluetooth network. The network consists of a mobile phone server and therefore is the platform very portable, but the platform also supports PC clients listening to the network for a high resolution overall view visualization. At this site we present CMAR and its features. We will also clarify what augmented reality is all about.