In recent years the usage of mobile devices and the expansion of their functionality by installing further applications have become very popular. Their frequent usage causes much faster battery discharging, and thus drastically limits the uptime of the devices and their applications. Hence, investigating and reducing the power consumption of mobile applications is one of the current, central challenges in software engineering. In this paper we propose an approach for profiling the power consumption of mobile applications and comparing their consumption for similar services. We show by example that such differences can be identified for two well-known email clients. We envision a repository or market place that allows users comparing and selecting applications based on energy labels and their personal requirements.