Genres embody typified discursive activity that is situated in an ecology of texts, people, and tools. Within these settings, genres help writers compose recognizable information artifacts. Increasingly, however, many professions are becoming mobile, and mobile technologies (e.g., personal digital assistants [PDAs]) are creating problems of translation as writers attempt to make genres work across contexts. Mobile devices uproot genres from their native contexts, undercutting their ability to mediate discursive activity. The semantically reduced design of PDA-accessible information magnifies these problems by obscuring, but not erasing, genre characteristics that tie information to its native context. Readers must assume the burden of composing meaningful information artifacts, work otherwise offloaded to genres. The author explores the nature of this composition burden in a case study of veterinary students. He finds that context and the degree of mobility both influence student perception of this composition burden. (Contains 1 table and 6 figures.)