Most calendar applications are designed around one familiar system: the Gregorian calendar.
But what if you want to work with different calendar systems, compare dates across calendars, or even create a calendar with your own months, weekdays and year structure?
That's the idea behind Universal Calendar, an open-source Flutter application I developed.
🌍 What is Universal Calendar?
Universal Calendar is designed for people who want more flexibility in how they organise, understand and manage time.
It brings multiple calendar systems into one application and goes further by allowing users to create entirely custom calendars.
✨ Key Features

  1. Multiple Calendar Systems The application includes seven calendar systems: Gregorian Julian Ethiopian Coptic Biblical (Hebrew) Islamic (Tabular Hijri) French Republican Users can explore different calendar structures and compare dates.
  2. Custom Calendar Creator This is one of the application's central features. Users can define their own: Number of months. Month names and lengths. Week lengths and weekday names. Year numbering and starting points. Leap-year rules. Special days. In other words, users aren't restricted to the calendar systems already included.
  3. Dual Calendar Comparison View and compare two calendar systems, making it easier to understand how different systems represent time.
  4. Events and Smart Alarms Universal Calendar supports: Single-day and multi-day events. Recurring events. Custom event durations. Multiple reminder intervals. Continuous alarm sounds and vibration until stopped or snoozed. Multiple notification tones.**
  5. ***Different Calendar Views* Choose between Month, Week, Agenda and Day views to organise your schedule.
  6. Christian Tools The application also includes: Bible verse of the day. Scripture memory tracker. Prayer requests. Prayer timer. Gratitude journal. Fasting tracker.
  7. PDF Export Export event lists and calendar layouts into PDF documents. 🛠️ Built With Flutter Dart Local data storage Android notification and alarm functionality The application is designed to work locally without requiring Firebase account synchronisation. 🎯 Why I Built It I wanted to explore something beyond the conventional calendar experience. Time can be represented in different ways, and people have different scheduling needs. I wanted to create an application that gives users more freedom to explore, organise and even define their own calendar structures. Universal Calendar is my attempt to bring those possibilities together in one application. 🔓 Open Source Universal Calendar is publicly available on GitHub. You can explore the source code, inspect the project and download available releases. GitHub Repository: https://github.com/KellyGlennIT/Universal-Calendar If you find the project interesting, feel free to explore it, share feedback or contribute. Built with Flutter. Made to explore time beyond the ordinary calendar.