Usability testing is one of the most used methods to define the level of usability of a software product. However, there is always uncertainty to determine the best method that complements user testing in a depth usability assessment. Nowadays, the concern of many software developers is to identify an appropriate methodology, whose evaluation methods could be capable of measuring all usability aspects of a user interface. For this reason, we conducted a heuristic evaluation as a preliminary step to the implementation of a usability test, in order to determine in which extent these methods complement each other, and establish the gaps which are covered by each of them. The heuristic evaluation was performed by five specialists in the field of Human-Computer Interaction, who identified a total of fifty-nine usability problems in a transactional web site. Subsequently, a usability test was conducted with the participation of eight postgraduate students of a master's program in Informatics Engineering. The results show that most of the usability problems which were detected during the usability testing, had already been identified by the heuristic evaluation. Nevertheless, there were significant differences in the importance that was given to each problem. Usability experts emphasized in aspects that were not relevant to end users.

Since usability is considered as a critical success factor for any software application, several evaluation methods have been developed. Nowadays, it is possible to find many proposals in the literature that address to evaluate usability issues. However, there is still discussion about what usability evaluation method is the most widely accepted by the scientific community. In this research, a systematic review was performed to identify the evaluation methods that have been more employed over the last three years in order to assess the level of usability of a software application. From these results, it has been possible to establish clear evidence about the current trends in this field. A total of 274 usability studies have allowed to reach useful information for scholars in this area.

Usability is currently one of the most important aspects of software quality. Developers are aware that if a software product does not meet user's expectations regarding usability, the entire project might fail. For this reason, several usability evaluation methods have emerged and nowadays are employed from early phases of the software development process. However, the literature reports a wide range of techniques for this purpose. In this way, the choice of a suitable method for a particular scenario has become a difficult decision. Through a systematic mapping review about the use of usability evaluation methods in software development contexts, we have identified the most commonly used techniques. A total of 228 case studies were selected for this review. We found that (1) Questionnaire, (2) User Testing and (3) Heuristic Evaluation were the most frequent. This study is intended to be a guide for scholars in this area.