Comparative Analysis of Usability and Security Performance of Android Graphical Authentication Mechanisms

Mobile authentication systems play a critical role in protecting sensitive information stored on smartphones and other portable devices. Among graphical authentication methods, Android Pattern Lock has gained widespread adoption because of its simplicity and ease of use. However, concerns regarding usability, predictability, and vulnerability to observation attacks continue to raise questions about its effectiveness. This study presents a comparative usability and security analysis of Android Pattern Lock and the Draw-A-Secret (DAS) graphical password scheme based on human characteristics. The study also evaluates the impact of visible and invisible joining node configurations on authentication performance. A mixed-method approach involving questionnaire-based evaluation and experimental analysis was adopted. Data were collected from 60 participants using usability metrics such as authentication time, login success rate, error rate, and perceived ease of use, alongside security metrics including password space, resistance to shoulder surfing, and observability. The results indicate that Android Pattern Lock provides superior usability performance, while DAS demonstrates stronger theoretical security. Visible joining nodes significantly improved usability, whereas invisible joining nodes enhanced perceived security by reducing observation-based vulnerabilities. The findings confirm the existence of a usability and security trade-off in graphical authentication systems and highlight the importance of human-centered considerations in authentication design. The study recommends that mobile authentication mechanisms should balance usability and security to improve both user experience and protection.