AidPulsate

The problem. Human trafficking survivors and people at risk of abduction are often deliberately cut off from the internet — captors confiscate data plans, disable Wi-Fi, or move victims to remote areas with no broadband coverage. Existing SOS and safety apps almost universally assume an internet connection is available, which makes them useless in the exact scenario they're meant to protect against. At the same time, cellular voice/SMS signal is frequently still present even where data isn't — cell towers carry SMS traffic on a separate, lower-bandwidth channel that works even in poor-coverage or data-restricted conditions. This gap between "no internet" and "no signal at all" is where most emergency apps fail silently, and where AidPulsate is designed to keep working. The solution. AidPulsate is a Flutter-based two-app system — a Victim app and an Admin/responder app — backed by Supabase, with a custom-built SMS fallback layer as the core differentiator. When the Victim app detects no internet via connectivity_plus, it doesn't just fail — it encodes the SOS event (event ID, device ID, sequence number, GPS lat/lon, timestamp, and an HMAC signature for authenticity) into a compact SMS payload and sends it to a dedicated SMS gateway phone. That gateway — a second Android device running its own listener — decodes and validates the payload, then forwards it to a Supabase Edge Function the moment it regains internet access, where it's deduplicated against a Postgres unique constraint and inserted as a real-time event for responders to see. Target users. Two distinct user groups: (1) potential trafficking victims or people in coercive-control situations, who need a way to raise an alert that is fast, hard to trigger by accident, and doesn't visually broadcast itself if their phone is being monitored; and (2) responders/case workers/NGO staff, who need an unambiguous, realtime, map-based dashboard to triage incoming alerts by severity and respond quickly. How users interact with it. A victim opens the app, triggers SOS in two taps with a brief cancel window to prevent false alarms, and the app silently handles the rest — capturing GPS, choosing online or SMS transport automatically, and queuing locally so no event is lost even through connectivity changes. A responder sees new alerts appear in realtime on a dashboard, with location history on a live map, and can acknowledge or resolve each case. What makes it creative and unique. Most emergency-alert apps stop working the moment internet is unavailable — exactly the condition traffickers can engineer. AidPulsate treats the SMS-fallback path as a first-class citizen of the architecture, not an afterthought, with authenticated payloads (HMAC), deduplication, and a purpose-built gateway device, rather than assuming SMS is a lesser or unreliable channel. Efficiency of the solution. By keeping the SMS payload minimal (a single-segment message) and pushing all validation/dedup logic server-side via Supabase Edge Functions, the system stays cheap to run, fast to send, and resilient to duplicate or delayed message delivery — critical properties when the stakes are a real emergency, not a demo convenience.