Introduction
According to Cisco, the number of mobile-connected devices has already exceeded the number of people on earth, while by 2017 there will be nearly 1.4 mobile devices per capita [1]. Nowadays users crave an “any-time-any-place” connectivity, using cutting edge devices such as smartphones, tablets, e-book readers and netbooks, among others. These high-end devices have bridged the gap between performance and hand-held size mobility, enabling the “on-the-move” use of bandwidth-hungry applications.