I need a beta version of a productivity-focused mobile application built for both iOS and Android. The goal is to deliver a stable, test-ready build that demonstrates the core workflow, clean UI, and smooth sync between devices. Key points • Core features: task creation, reminders, simple calendar view, and basic cloud backup. • Platforms: native or cross-platform stack that meets Apple App Store and Google Play guidelines. • Code quality: clearly commented, modular structure, and version-controlled in a private Git repository. • Handoff: deployed builds (TestFlight and Google Play Console internal test), source code, and setup instructions. Please outline the tech stack you recommend, estimated timeline, and any prior productivity apps you have shipped. I’m ready to move quickly once I see the right approach.