Mobile/cloud applications are distributed over users' mobile devices and across back-end cloud servers around the world. As a consequence, application programmers now face deployment decisions that were visible only to designers of large-scale distributed systems in the past. These decisions include where data and computation should be located, what data should be replicated or cached and what data consistency level is needed. We are working on how to separate deployment from applications, while still giving application programmers control over performance trade-offs in the Sapphire project.