[ACM]
Offloading tasks to cloud is one of the proposed solutions for extending battery life of mobile devices. Most prior research focuses on offloading computation, leaving communication-related tasks out of scope. However, most popular applications today involve intensive communication that consumes a significant part of the overall energy. Hence, we currently do not know how feasible it is to use offloading for saving energy in such apps. In this paper, we first show that it is possible to save energy by offloading communication-related tasks of the app to the cloud. We use an open source Twitter client, AndTweet, as a case study. However, using a set of popular open source applications, we also show that existing apps contain constraints that have to be released with code modifications before offloading can be profitable, and that the potential energy savings depend on many communication parameters. We therefore develop two tools: the first to identify the constraints and the other for fine-grained communication energy estimation. We exemplify the tools and explain how they could be used to help offloading parts of popular apps successfully.