Mobile Developer

Create realistic, interesting, and extremely challenging mobile coding tasks for frontier AI models using your preferred repositories. Design problems that require strong mobile engineering skills, such as tracking down subtle bugs, building non-trivial features, handling application state and lifecycle, or improving performance. Develop tasks relevant to your expertise: cross-platform applications using TypeScript, JavaScript, or Dart; iOS applications using Swift; or Android applications using Kotlin. For each task, define the problem, build a reproducible environment, and write deterministic verifiers that accept correct solutions across different valid implementations while rejecting incorrect, incomplete, or hard-coded approaches. Provide a reference solution showing how the task can be solved.