How it works
From SOS to response, with or without a network.
An SOS is saved on the phone, sent every way that's available, and passed hand to hand by nearby phones until one of them reaches the Internet and a responder takes ownership.
- 01
Prepare before anything happens
Add your trusted contacts and turn on mesh mode. Contacts are cached on your phone so an SOS can reach them without a server. An SOS can also be sent without signing in, over the mesh and by SMS.
- 02
Send an SOS, or let detection start one
Tap SOS, choose a category and confirm during a 5-second countdown. Crash or earthquake detection can also start one after a countdown you can cancel. The SOS is saved on your phone, with GPS if available, before anything is sent.
- 03
It goes out every way it can
Over the mesh to nearby ResQNet phones, which keep a copy and pass it on (store-and-forward). As a pre-filled text to your trusted contacts and local police or disaster numbers, if there's cell signal. And straight to the ResQNet server, if your phone has Internet.
- 04
The first phone with Internet uploads it
The server checks the sending phone's signature, credits the SOS to you rather than the relaying phone, and stores it once even if several phones upload it. Your ResQNet trusted contacts get a generic push notification.
- 05
Responders take ownership
The SOS enters the responder incident queue and moves through acknowledged, assigned, en route, arrived, assisting and resolved. Marking yourself safe or cancelling is recorded, but only a responder closes the incident.
When networks fail
How an SOS travels with no signal.
Step through it below. This is a concept demonstration of the protocol, not a live network.
Phone A
Needs help · no signal
SOS created
Phone B
Offline
Waiting
Phone C
Offline
Waiting
Phone D
Offline
Waiting
Phone E
Has Internet
Waiting
ResQNet server
Verifies origin, stores once
Waiting
Trusted contacts
Generic push, no message text
Waiting
Responder portal
Incident queue and workflow
Waiting
Step 1 of 7: No mobile network or Internet. Phone A sends an SOS. It is saved on the phone first, with location if GPS has a fix.
This animation shows the order of events only. How far one phone reaches another depends on the phones, radio conditions, terrain and buildings; ResQNet will publish measured results from field tests rather than a promised range. The responder operations portal in the last step is built but not yet deployed, and ResQNet is not integrated with any emergency agency today.
Resilient communication
What's implemented today, and what's ahead.
Mesh and offline communication are easy to overstate. Here's exactly what ResQNet does today, and what it doesn't yet.
Implemented today
- Direct phone-to-phone relay over Bluetooth and Wi-Fi Direct (Google Nearby Connections on Android, MultipeerConnectivity on iOS).
- Multi-hop store-and-forward: relays keep other people's SOS alerts and pass them to phones they meet later; the first phone with Internet uploads them. Tested in simulation, A→E.
- Signed SOS: relays can't change the text or location; signed hop limits and expiry (24 hours by default); duplicate detection that survives restarts.
- Server-side signature verification and de-duplication for relayed SOS alerts.
- Responder operations portal (incident queue, workflow, assignment, map, audit log). Built and tested, not yet deployed.
Not yet done
- Physical tests across several real phones, with published range and delivery results.
- Ordinary chat over the mesh (today chat messages wait for Internet).
- Encryption of mesh payloads (today they are signed, not encrypted).
- Connection to verified official disaster-alert feeds (the integration exists; no source is connected yet).
Relay depends on other people nearby running ResQNet with mesh mode on. Range depends on the phones, terrain, buildings and interference; no range is claimed until it has been measured. On iOS the mesh works only while the app is open. ResQNet extends reach on the ground; it does not guarantee that a message gets through.
How the offline mesh works
Four things to know about the mesh.
No Internet needed between phones
Nearby phones running ResQNet talk directly over Bluetooth and Wi-Fi Direct. No cell tower, router or server sits in the middle.
Range is not fixed
How far one phone reaches another depends on the hardware, walls, terrain and interference. ResQNet will publish measured field-test results, not a promised distance.
Other people's phones carry it
The mesh only exists where other people are running ResQNet with mesh mode on. On Android, whether it keeps working in the background depends on the phone's power management; on iOS, expect it to work only while the app is open.
Internet and SMS still help
Any phone that has Internet uploads the SOS. Your phone can also open a pre-filled text to your trusted contacts, which needs ordinary cell signal. The server adds to the mesh; it doesn't replace it.
For civilians
Built for the places where the network runs out.
ResQNet is for anyone who could be cut off when something goes wrong.
- People caught in a disaster
- Trekkers and hikers
- Tourists in unfamiliar places
- Rural and remote communities
- Forest and field workers
- Stranded travelers
Example scenarios
Earthquake
Towers are down and the network is jammed. You send an SOS; nearby phones running ResQNet pick it up and carry it towards someone with a working connection. If you're fine, one tap on "I am safe" tells the phones around you.
Flood or cyclone
You're cut off with patchy signal. The SOS is saved on your phone first, so it isn't lost if sending fails, and ResQNet keeps trying over the mesh and the Internet as either comes back.
Landslide on a mountain road
A blocked road strands a bus of travelers. Phones in the group form a local mesh, and any traveler who regains signal further down the valley can upload the SOS alerts their phone is carrying.
Lost or injured on a trail
No coverage on the ridge. Your SOS carries your GPS position when the phone has a fix, and passes to other hikers' phones that come within range later, even hours afterwards.
Wildfire evacuation
Everyone is moving at once. Mesh hazard reports, such as a fire or a blocked road, spread between nearby phones as unverified community reports, separate from official alerts.
Can't reach your phone
On-device crash and earthquake detection can start an SOS after a countdown you can cancel. These detectors still need real-world testing and will sometimes miss events or misfire.
These are illustrations of how ResQNet is designed to help, not accounts of real deployments. Always contact local emergency services when you can. ResQNet also lists local emergency numbers for the country you're in, where they're included in the app.