The best way to prevent data leakage from a lost mobile device is data encryption on the mobile device. Data encryption is a technique that transforms data into an unreadable format using a secret key or algorithm. Data encryption protects data from unauthorized access or disclosure in case of loss or theft of a mobile device.
Complex password policy for mobile devices, triggering of remote data wipe capabilities, and awareness training for mobile device users are useful measures to enhance data security on mobile devices, but they do not prevent data leakage as effectively as data encryption. A complex password policy can be bypassed by brute force attacks or password cracking tools. Remote data wipe capabilities depend on network connectivity and device power availability. Awareness training for mobile device users can reduce human errors or negligence, but it cannot guarantee compliance or behavior change. References: CISA Review Manual (Digital Version): Chapter 5 - Information Systems Operations and Business Resilience