I already have the full source code for a mobile app that targets both iOS and Android. The current build works, yet it feels rough around the edges—screens lag, features behave inconsistently, and the interface still carries a few placeholder elements. I need an experienced developer who can dive into the existing codebase, streamline it, and deliver a noticeably smoother experience. Here is what I expect: • Revamped user interface that matches the designs I will supply and respects each platform’s native guidelines. • Adjusted or newly added functionality where current features fall short of the spec (I’ll outline these in detail once we start). • Performance tuning so the app loads quickly, scrolls without stutter, and shows no memory-related crashes on common devices. • Clean, well-commented code pushed to my Git repository, along with test builds for both platforms that I can install directly. • A short hand-off report summarizing every change and the measurable performance gains achieved. I will provide the design assets, current source, and a prioritized bug/feature list on day one. If you are comfortable working with a dual-platform codebase and can demonstrate previous success in UI polish, feature extension, and performance optimization, let’s talk timelines and get this app feeling truly production-ready.