Nowadays, there is a growing concern about the energy consumption of the ICT industry. This fact has given rise to a lot of energy saving research activities, which mainly focus on the hardware side of computational systems. However, it is tempting to suppose that only hardware dissipates power, not software. This paper discusses several software methods, which could be explored to develop energy-efficient mobile techniques. We argue that the development of applications that consider the energy saving, as one of their requirements, can result in a significant final energy saving because solutions will be part of the own software and they do not depend of external resources to obtain a lower consumption.