A single code-base or native approach is fine, as long as the finished product runs smoothly on both iOS and Android. The assignment spans concept refinement, UX/UI design, coding, testing, and final submission to the App Store and Google Play. Core scope • Craft a clean, intuitive interface that feels at home on each platform. • Build out the essential productivity workflow (exact feature list will be finalised together). • Add secure sign-in and cloud-based data sync so users can move effortlessly between devices. • Hand over fully documented source code plus release-ready builds that pass Apple and Google review. Acceptance criteria • Identical feature set and stable performance on the latest versions of iOS and Android. • Zero critical bugs after one-week user acceptance testing. • Full compliance with both stores’ current guidelines. All copy, graphics, and any required APIs can be coordinated as we go; just flag third-party services that carry licence fees before integrating them.