Staff Scheduling Web & Mobile App

I need a streamlined web and mobile application that lets our managers and office staff build, publish, and adjust work schedules, then assign tasks to the right people in real time. The core goal is to replace scattered spreadsheets and email threads with one intuitive platform that keeps everyone on-track and accountable.

Scope
• A responsive web portal where managers create weekly rosters, drag-and-drop shift changes, and track task completion.
• Companion Android and iOS apps so staff can view their shifts, accept or decline changes, and mark tasks done from the field.
• Role-based access: managers see the full dashboard, reports, and analytics; office staff see only their shifts, tasks, and limited messaging.
• Secure database with audit logs, so every edit can be traced back to the user and timestamp.
• Push and email notifications for new shifts, updates, and overdue tasks.

Acceptance criteria
1. A manager can build a schedule in the web app and have it appear instantly on an employee’s phone.
2. Staff actions (accept, swap, complete) sync bidirectionally within five seconds.
3. All data is encrypted in transit and at rest, following current best practices.
4. The interface loads in under three seconds on a standard 4G connection.

Tech flexibility
I’m open to React / React Native, Flutter, or a similar modern stack, as long as it delivers smooth cross-platform performance and a maintainable code base.

Please outline your preferred stack, timeline, and any similar projects you’ve shipped so I can choose the best fit to bring this scheduling tool to life.