We are building upon a pilot project that investigated the role of cell phone trouble among teens in Washington, DC (2013-2014 — funded by the Smithsonian). By ethnographically describing cell phone breakdowns in five contexts (infrastructure, hardware, software, conversation, and etiquette) we seek to analyze these troubles among teens, some of the heaviest users of these devices, and some of the most vulnerable to their failure. The results will provide a detailed account of the actual uses of these communicative technologies, revealing background assumptions about relations between materiality and semiosis. In the process of carrying out this research, we will develop methods for analyzing mediation as an interaction between the material and the semiotic; our employment of video data will be significant in this respect, revealing not just the words participants use, but also the physical objects to which they are attending in the course of their communicative practices. And finally, on the level of broader impacts, we anticipate that our results will contribute to ongoing debates about teen dependence on these devices role of technology in identity production, and the integration of technology into households and learning environments.