Nowadays, more than 70% of internet users use mobile devices to surf the internet. Designing user friendly interfaces for mobile devices is a major challenge. The physical dimensions of smartphones and tablets provide very limited space for the presentation of content, as well as for interactions. The context of use is also difficult to predict, for example, mobile user interfaces also need to function perfectly when on the go. When entering the bus, the user does not want to lose the just tediously entered text message. Establishing user-centered design
during the entire development process of mobile applications and websites ensures a high mobile usability.