Comparison of energy consumption between a mobile device and a collection of dedicated devices

It is often considered that general purpose mobile devices, such as smartphones, consume more energy than dedicated devices, e.g. MP3 players. This is typically associated with the application specific hardware that is optimized for its particular function. While this assumption might be true for a single function, there exists the fact that a modern smartphone combines multiple functions which traditionally only could be provided by a large collection of dedicated devices. The energy consumption of a multi-functional mobile device could be less than the augmentation of the dedicated devices. In addition, there can be benefits related to convenience and agility. To get better understanding, a study was made to compare the power consumption of some typical use cases between a mobile device and dedicated devices (each with a dedicated function). Our findings indicate that in the tested cases the mobile device can be significantly more energy efficient and more environmental friendly than combining the dedicated devices for the same set of functionalities. It should be understood that the results are not statistically significant over a wide range of markets and should not be considered as a generic claim. However, the findings will provide a starting point for discussions and for possible future work.