As mobile devices grow increasingly in popularity within the student community, novel educational activities and tools, as well as learning approaches can be developed to get benefit from this prevalence of mobile devices (e.g. mobility and closeness to students' daily lives). Particularly, information security education should reflect the current trend in computing platforms away from the desktop and towards mobile devices. This paper discusses a case study of a learning approach that aims at taking advantages of the benefits of mobile devices and the best practices in learning information security, as well as promoting students' interests and increasing their self-efficacy. The learning approach uses two Android learning apps to enhance students' hands-on skills on firewall filtering rules implementation, by practicing network traffic filtering outside the traditional laboratory activities, in the real-world environment; i.e., anywhere and anytime, at the students' convenience. Practically, the two Android apps are a firewall app and a packet generator app; both apps are freely available at Google Play Store. Based on statistics from the Google Play Store, in about one and a half years, the packet generator app turned popular with over 20,000 downloads worldwide and a 3.75 users' rating. A comparative analysis of various existing Android firewall apps with the proposed firewall app emphasizes its significance. The impact of the Android apps on the students' performance in terms of achieving the course outcomes is also discussed.