Mobile application security testing is important to identify vulnerabilities and protect sensitive user data. The key concepts of mobile app security testing include authentication, authorization, availability, confidentiality, integrity and non-repudiation. Common mobile security threats include malware, spyware, privacy threats and vulnerable applications. Effective security testing employs strategies like strong authentication, encryption, access control and session management. The testing methodology involves profiling the app, analyzing threats, planning tests, executing tests, and providing daily status reports. Deliverables include management reports, technical vulnerability reports, and best practices documents.