What layout is most suitable for developing a mobile app?

The most suitable layout for developing a mobile app is the phone-specific layout. This layout is specifically designed to cater to the smaller screen size and touch interactions typical of mobile devices. A phone-specific layout optimally utilizes the limited screen space by arranging elements in a way that enhances usability and user experience.

It focuses on providing a streamlined interface and allows for easier navigation and interaction on mobile devices, ensuring that users can access the app's features without unnecessary complexity or clutter. By conforming to the specific dimensions and capabilities of phones, this layout maximizes performance and engagement.

In contrast, while responsive layouts can adapt to various screen sizes and are useful in different contexts, they may not fully leverage the unique design considerations necessary for mobile environments. Tablet-specific layouts are designed for larger screens and may not be as effective for smaller phone displays. Web-specific layouts, on the other hand, are tailored for traditional web browsers and may not optimize the mobile experience, which is crucial for app development aimed at handheld devices.