The potential of Web Augmentation lies in the fact that all users need to adapt the content, style or behavior of the web pages they visit. The reason for this is that all human beings are different in desires and needs, but everybody accesses web pages designed for the general public and this cannot satisfy everyone. Web Augmentation tools have different objectives, for example when modifying content, style or behavior. Similarly, some tools are designed to adapt web pages on mobile devices and others, on the contrary, on computers. This mapping study aims to provide information on the trends of the last years in relation to Web Augmentation for each of the features of Web Augmentation tools. By analyzing the data provided, information can be extracted to design new mechanisms for the creation of new Web Augmentation tools in the future.