Cross-Platform Library & Portfolio Apps

I need two production-ready applications built from the ground up—one to run our internal library and another that lets my investors track their stock portfolios in real time. Both products must work seamlessly on iOS, Android, and any modern browser, with a single codebase where possible to keep maintenance and costs under control. What matters most to me is reliability, an intuitive interface, and smooth performance across devices. On the library side, think cataloguing, check-in/check-out, user accounts, due-date reminders, and simple admin controls. The portfolio tracker should pull live market data, update holdings automatically, show basic analytics, and push configurable alerts. Data security, role-based access, and clean dashboards are non-negotiable for both apps. I’m open to your design ideas and branding proposals as I don’t have fixed guidelines yet, but consistency between mobile and web is essential. If you prefer Flutter, React Native, or another cross-platform stack, feel free to recommend it—just justify how it keeps performance high and total cost reasonable. To help me shortlist quickly, please include links, screenshots, or store URLs that demonstrate past work on comparable cross-platform projects. A brief note on the tech you used and any measurable results (downloads, uptime, user feedback) will really help. Deliverables: • Two fully tested, deployable applications (mobile & web) • Source code with clear documentation • Basic admin panels and installation guides • Post-launch support window long enough for initial fixes I have to stay within a lean budget, so pragmatic solutions, reusable components, and transparent timelines will set your proposal apart. Looking forward to seeing what you’ve already built and how you can bring these ideas to life.