Northstar is an on-device personal safety app built at LA Hacks 2026 that guides injured hikers through emergency response entirely offline. Built by Gene Iwasaki, Alex Bonev and Vidhu Venugopal, Northstar tackles one of the most dangerous gaps in outdoor safety: what happens when you fall on a trail with no cell signal and no one around.
What it solves
Over half of hiking-related injuries are caused by slips and falls, and most happen on trails where mobile data is limited or unavailable. After an injury, finding help can feel impossible. Northstar fixes that by building a complete emergency response system that works entirely without internet and can act on your behalf even if you are unconscious.
What it does
Northstar detects falls automatically and immediately begins a hands-off emergency response. It starts a voice-activated digital triage to assess the injury, measures heart rate and blood pressure using the phone's back camera via Photoplethysmography, dispatches a swarm of AI agents to find the nearest care center and other vital information, and then uses satellite connectivity to call your emergency contact and send an SMS with your full injury assessment.
How it works
Northstar is built on React Native with Expo and uses ZETIC Melange to run two on-device AI models with zero cloud dependency. Fall detection combines accelerometer spike detection with YAMNet, an on-device audio classification model that detects sounds of pain. The voice triage runs on Qwen 3.5 4B deployed via ZETIC Melange. A swarm of fetch.ai agents handles information retrieval in parallel. Emergency calls and SMS are routed through Twilio and ElevenLabs.