AlertSign – Smart Calendar & Reminder Alert System
AlertSign is a sophisticated cross-platform calendar intelligence application built with Flutter, designed to deliver real-time full-screen alerts for upcoming calendar events and reminders. It bridges the gap between passive calendar notifications and attention-grabbing, context-aware alerts ensuring users never miss a meeting or deadline.
The app integrates deeply with native iOS EventKit to access calendar events, reminders, and travel time data. It provides granular control over alert triggering through smart filtering, exclusion rules, and work-hour enforcement. A native iOS Home Screen Widget offers a live, glanceable view of upcoming events, while background refresh tasks keep widget data up to date even when the app is closed.
AlertSign is designed for professionals managing complex calendars across multiple sources (iCloud, Google, Exchange) who require reliable, intelligent alerting aligned with their schedule context.
See It In Action
Real screens from the shipped product crafted for an intuitive, smooth, and delightful user experience.
Key Features
Real-Time Full-Screen Alerts :
- Overview : Full-screen alert system for upcoming events and reminders
- Features : Live countdown timer, event details, alert queue navigation, sound playback, join meeting button, dismiss and pause actions
Native Calendar and Reminder Integration :
- Overview : Deep integration with iOS calendar system
- Features : Multi-source calendar support, reminder fetching, attendee data, alarms, travel time, and long-term event tracking
Home Screen Widget (iOS) :
- Overview : Live widget for upcoming events
- Features : Multiple sizes, color-coded entries, meeting indicators, background refresh, and quick access to app
Smart Alert Filtering :
- Overview : Intelligent filtering of alerts
- Features : Accepted events only, alarm-based filtering, video-only events, all-day event control, today-only mode
Exclusion Rules :
- Overview : Rule-based filtering system
- Features : Pattern matching, field targeting, case sensitivity, and persistent rules
Work Hours Enforcement :
- Overview : Alerts respect defined working hours
- Features : Enable/disable mode, per-day configuration, custom time ranges, automatic suppression
Pause / Snooze Alerts :
- Overview : Temporarily disable alerts
- Features : Timed or indefinite pause, visual indicator, automatic resume
Multi-Calendar and Reminder Selection :
- Overview : Manage multiple data sources
- Features : Toggle calendars/reminders, account labeling, and color coding
Custom Alerts :
- Overview : Create alerts independent of calendar events
- Features : Custom title, notes, trigger time, and persistent storage
Travel Time Display :
- Overview : Shows travel time for events
- Features : Displays travel duration and optionally adjusts alert timing
Meeting Link Detection :
- Overview : Automatically detects meeting links
- Features : Supports Zoom, Meet, Teams, and provides one-tap join
Attendee Tracking and RSVP Status :
- Overview : View participant details
- Features : RSVP tracking, organizer identification, and attendee list
Customizable Alert Sounds :
- Overview : User-selectable alert sounds
- Features : Multiple sound options, silent mode, and preview
Multi-Step Onboarding :
- Overview : Guided setup experience
- Steps : Permissions, calendar selection, signup, subscription, and demo alert
Custom Per-Event Alert Time :
- Overview : Customize alert timing per event
- Features : Set custom reminders and save preferences
Permission Management :
- Overview : Handles required system permissions
- Features : Calendar, reminders, notifications, and in-app warnings
Subscription and Paywall :
- Overview : Premium feature access system
- Features : Subscription plans and purchase flow
Background Persistence and Terminated State Recovery :
- Overview : Ensures alerts work even when app is closed
- Features : Background updates, data sync, and duplicate alert prevention
Third Party SDKs & Libraries
Carefully selected integrations powering this project's core functionality.
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