The Mobile Compatibility Checklist is a comprehensive tool for evaluating the usability of websites and web applications on mobile devices. It covers a range of areas, from mobile-friendly features such as responsive design, to device-specific areas like touch, tilt and swipe navigation. The checklist also covers performance and compatibility testing, ensuring that a site or application works across all devices and browsers. It also covers accessibility requirements, ensuring that the site is usable by people with disabilities. The checklist is a great way to ensure that all mobile users have a good experience when using a website or web application.