Mobile User Interface Implementation and Responsiveness Questions

Designing and building mobile user interfaces that adapt and perform well across different screen sizes, pixel densities, orientations, and device form factors. Core skills include mastery of platform layout systems and idioms such as constraint based layouts, declarative UI frameworks, and responsive layout primitives; handling device rotation and configuration changes while preserving UI state; implementing adaptive and fluid layouts for phones, tablets, foldables, and multiwindow modes; accessibility considerations including proper semantics, focus order, contrast, and scalable text; touch and gesture handling, hit targets, and input responsiveness; performance optimization for rendering, view hierarchies, and animations; safe area and inset handling, resolution and density independence, and support for platform specific patterns on Apple iOS, Google Android, and cross platform frameworks. Candidates may also be evaluated on testing and debugging strategies for UI, using layout inspectors, automated UI tests, and strategies for progressively enhanced designs.