LifeLink

A mobile communication concept for the moments when internet and GSM infrastructure are unavailable.

LifeLink combines nearby-device communication, SOS workflows, and offline guidance in one emergency-focused experience.

Mobile

Role: Connection flows & database layer
Team: 4-person AppJam team
Timeframe: AppJam 2025 sprint
Status: Hackathon build
Platform: Flutter mobile app

The project at a glance

Context

Created with Mehmet Ali Donmez, Memduh Alpsoy, and Merve Canpolat during Bandirma University AppJam 2025. My contribution focused on connection flows and the main database layer.

Project overview

LifeLink is a Flutter-based emergency communication app created at Bandirma University AppJam 2025 by Mehmet Ali Donmez, Baver Arslanargun, Memduh Alpsoy, and Merve Canpolat. It helps people stay connected during earthquakes and other disasters even when internet and GSM infrastructure are unavailable. By combining peer-to-peer mesh communication, location-aware SOS requests, offline emergency guidance, and optional gateway synchronization, the app focuses on practical disaster resilience. My contribution centered on connection flows and the main database layer.

Why this exists

Problem & direction

Problem

Earthquakes and similar disasters can make internet and GSM-dependent communication unreliable exactly when people need to share location and help requests.

Goal

Explore an offline-first mobile flow that keeps nearby communication, location-aware SOS requests, and emergency guidance accessible during infrastructure loss.

How it comes together

Experience flow

Flow notes are being prepared

The section is reserved for a verified step-by-step product flow. It will be completed with the next set of project details.

See the work

Evidence & media

Product walkthrough in preparation

Screenshots and a concise walkthrough will be added after the project assets are curated.

What it is made of

Technical shape

Feature set

Peer-to-peer mesh communication over Nearby Connections, Wi-Fi Direct, and Bluetooth
Offline messaging and device discovery without internet access
Automatic reconnection and multi-device mesh propagation
Emergency alert flow with vibration, flashlight, whistle, and timed SOS fallback
Location-based help requests with rescue status tracking
Offline guidance for first aid, earthquake response, and CPR
Foreground/background services for persistent connectivity
Gateway sync model for devices that regain internet access

Architecture

Flutter application structured around core services and feature modules: mesh networking, chat, notifications, heartbeat tracking, gateway synchronization, and offline guidance screens. Native Android mesh integration, local persistence, and optional cloud sync work together to support an offline-first disaster communication flow.

Stack

FlutterDartNearby Connections APISQLiteFirebase FirestoreGeolocatorFlutter MapOpenStreetMaplocal notificationsforeground services

Engineering notes

Decisions & challenges

Decision log coming next

Technical decisions and challenges will be added after the contribution and implementation notes are reviewed.

Reflection

What I learned

LifeLink gave me hands-on experience in mobile teamwork under hackathon pressure, offline-first system design, peer-to-peer connectivity, and building reliability-focused features for high-stakes real-world emergency scenarios.

Where it can go

Next steps

No speculative roadmap

Concrete next steps will be published when they are selected. Until then, the status above is the source of truth.