The increasing complexity of mobile phones directly affects their reliability, while the user tolerance for failures becomes to decrease, especially when the phone is used for business- or missioncritical applications. Despite these concerns, there is still little understanding on how and why these devices fail and no techniques have been defined to gather useful information about failures manifestation from the phone. This paper presents the design of a logger application to collect failure-related information from mobile phones. Preliminary failure data collected from real-world mobile phones confirm the proposed logger is a useful instrument to gain knowledge about mobile phone failure?s dynamics and causes.