Permission Ruler [Root] represents a specialized utility application designed exclusively for rooted Android devices, offering unprecedented control over application permissions beyond standard system capabilities. Developed by Stefano Siano, this tool addresses growing privacy concerns by enabling users to manage when and how applications access sensitive device features, particularly focusing on preventing unauthorized background access when the screen is inactive. The application's core functionality revolves around its ability to automatically revoke dangerous permissions when the device screen turns off, then restore them when activated again. This includes monitoring and controlling access to microphone, camera, location data, and other sensitive permissions that could potentially be exploited. The system requires careful configuration, with users needing to manually specify which permissions to manage for each application, creating a tailored privacy protection system. A critical safety feature involves pausing the application before uninstallation to ensure all permissions are properly restored to avoid breaking essential app functionality. User experience centers around a straightforward interface that lists all installed applications with their respective permissions, though the interface lacks modern design elements. Navigation requires technical understanding, as users must manually configure rules for each application rather than relying on automated profiles. Real-world usage demonstrates effectiveness in preventing background data collection, particularly for social media applications and games that frequently access unnecessary permissions. The application performs reliably on properly rooted devices, though setup time varies significantly depending on the number of applications requiring permission management. No specific user reviews are available for detailed analysis, though the 4.15 rating suggests generally positive reception among its niche user base. The absence of detailed feedback indicates either limited adoption or users not engaging with review platforms, which is common for specialized root applications targeting advanced Android users. The application's primary strength lies in its granular permission control unavailable to non-rooted devices, providing genuine privacy protection against background data harvesting. However, significant limitations include the root requirement limiting its audience, potential stability issues if not properly configured, and the manual nature of permission management becoming cumbersome with numerous applications. Ideal for security researchers, privacy advocates, and technical users willing to maintain rooted devices for enhanced control over their digital privacy.