摘要:Nowadays, instant messaging applications (apps) are one of the most popular applications for mobile devices with millions of active users. However, mobile devices present hardware and software characteristics and limitations compared with personal computers. Hence, to address the usability issues of mobile apps, a specific methodology must be conducted. This paper shows the findings from a systematic analysis of these applications on iOS mobile platform that was conducted to identify some usability issues in mobile applications for instant messaging. The overall process includes a Keystroke-Level Modeling and a Mobile Heuristic Evaluation. In the same trend, we propose a set of guidelines for improving the usability of these apps. Based on our findings, this analysis will help in the future to create more effective mobile applications for instant messaging.