Inspiration- This project was inspired by the need for a hands-free emergency alert system for situations where a person cannot manually call for help, such as medical emergencies, unsafe environments, or sudden panic.
Existing safety apps often require manual interaction, so this project explores a more automated approach using voice-triggered activation, live location sharing, and instant contact alerts.
The idea was to build something that can respond faster than human action in critical situations using modern web technologies like speech recognition and GPS tracking.
What it does- This app is a voice-activated emergency safety system. When the user speaks a pre-set safe word, it automatically triggers an emergency response.
It then:
Shares real-time GPS location Sends battery status Shares medical information Alerts emergency contacts in priority order Continuously updates location during the emergency Gives a short countdown to cancel false triggers
How we built it- We built this project as a full-stack web application using React and Supabase.
We used the Web Speech API to detect a predefined safe word through voice recognition. The Geolocation API captures real-time location during emergencies. The Battery API sends device battery status for context. React + TypeScript powers the frontend with a responsive UI. Supabase handles authentication, database storage, and real-time data (profiles, contacts, emergency logs). An Edge Function triggers emergency alerts and sends data to emergency contacts in priority order. A countdown system was added to prevent accidental triggers before activation.
Challenges we ran into-
Voice recognition reliability: The Web Speech API is not fully consistent across browsers and often stops in background tabs, making continuous listening difficult. Location permissions: Getting accurate and continuous GPS updates required strict handling of browser permissions and user consent. Battery API limitations: Battery Status API is not supported in all browsers, which made fallback handling necessary. False triggers: Preventing accidental safe-word activation required adding a countdown and cancel mechanism. Secure data handling: Managing sensitive medical and location data safely using Supabase Row Level Security was critical. Real-time updates: Keeping emergency location updates smooth without overwhelming the backend required optimization.
Accomplishments that we're proud of-
Building a voice-activated emergency system that actually works in real-time conditions Successfully integrating live GPS tracking with emergency alerts Handling sensitive medical and location data securely using Supabase Creating a smooth end-to-end emergency flow (trigger → countdown → alert → tracking) Designing a system that focuses on real-life safety impact, not just a demo project Combining multiple browser APIs into one working full-stack application
What we learned-
-How to build a full-stack application using React, TypeScript, and Supabase -Working with browser APIs such as Web Speech API, Geolocation API, and Battery API -Designing a real-time system that responds to user actions instantly -Implementing secure authentication and Row Level Security (RLS) in Supabase -Structuring an emergency workflow system (trigger → verification → alert → tracking) -Handling real-world browser limitations and permission constraints -Improving reliability with safeguards like countdown timers and cancel options
What's next for Safety Zone-
-Adding SMS and WhatsApp alerts using services like Twilio for more reliable emergency communication -Building a mobile app version (React Native or Flutter) for better background performance and push notifications -Introducing smartwatch and wearable integration for one-tap or voice-triggered SOS -Adding offline fallback modes so basic alerts can still trigger without stable internet -Integrating geofencing-based safety alerts for predefined safe and unsafe zones -Improving voice detection reliability with custom wake-word models or AI-based speech recognition -Adding emergency services integration where legally supported (local helplines/dispatch systems) -Expanding accessibility with multi-language support
Built With
- 18
- api
- auth
- battery
- css
- edge
- frontend
- gps
- medo
- postgresql
- react
- shadcn/ui
- speech
- supabase
- tailwind
- typescript
- vite
- voice
- web
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