While screen mirroring is an integral part of many video mediated collaborations, current systems are limited in their ability to include ad hoc screen mirroring from personal devices of collocated participants on each end of a video call. In this paper we introduce a system that addresses this limitation by enabling lightweight multi-user wireless smartphone mirroring within a video call. The system enables multiple smartphones to share both digital content as well as physical artefacts when mirroring the live view from the smartphone camera feed. We present a study of the system in use for a distributed design task. The findings explore how shared access to screen mirroring facilitates a fluid switching of floor control in the meeting and smooth interleaving of individual, sub group and full group shared activities. Further, the findings highlight the importance of smartphone mobility in enabling access to screen mirroring from the sites of individual work and sites of various physical artefacts and the significance of this for the dynamics of a video mediated collaboration.