Smartphones are one of the fastest-growing and most popular consumer devices introduced in the last decade, and the media environment is also changing dramatically. However, there is still a lack of research on recognizing smartphones as media and understanding their usage behavior. This study aims to understand smartphones? mobile application usage patterns from a media combination perspective by identifying mobile application repertoire and killer applications based on demographic segmentation. In this study, we propose the Weighted Formal Concept Analysis to specify the preference of mobile applications and identify their repertoires. The preference of mobile application evaluates the following four aspects in combination: relevance, commonlyshared, conformance, and contribution viewpoints. We conducted a case study, which identified the mobile application within-group and across-group repertoires based on the proposed method, and also discovered that mobile repertoire varies with not only age and gender but also their combinations.