Keryx Maps
The map that works when the network doesn’t.
An offline-capable mapping and alerting system designed for resilience, privacy, and real-world navigation under failure conditions.
From the founder
Keryx Maps started with a simple frustration: the apps we trust to get us somewhere are the first things to fail when it actually matters. The day a hurricane lands, a wildfire jumps a ridge, or the grid drops, the map app on your phone goes blank.
I wanted a map that assumed the worst day, not the best one. So we built Keryx around three rules that don’t bend: the maps live on your device, the routing runs on your device, and the alerts that reach you are tied to where you actually are.
It’s the app I wanted on my own phone, for my own family. If it earns a place on yours, that’s the whole point.
Three Rules That Don’t Bend
Every other decision in Keryx Maps follows from these three commitments.
Maps live on your device
Download once, use forever. No expiring tiles. No "offline area" re-download nag every thirty days. The maps you have today still work a year from now.
Routing runs on your device
No signal, no server, no leaked location data. Your route is calculated where it is used.
Alerts tied to where you are
Hazards overlapping your downloaded regions reach you. Noise from across the country does not. A small set of global events (major hurricanes, M6.5+ earthquakes, volcanic eruptions, radiation, severe space weather) fire regardless.
What Keryx does
Six capability areas, each engineered to keep working when the network or the grid does not.
Offline-first navigation
- •Vector maps downloaded by region — state, country
- •Turn-by-turn routing powered by Valhalla, computed on-device
- •Topographic overlays with contour lines for backcountry use
- •Custom vehicle profiles (car, truck, bike, foot, RV)
- •Offline POI search (gas, food, lodging, parks, trails) from OpenStreetMap and Overture
- •Driving Mode HUD optimized for in-vehicle use
Hazard awareness
- •45+ authoritative sources (USGS, NOAA/NWS, NHC, USGS HANS, NASA DONKI, EPA, international meteorological agencies)
- •Local alerts tied to your downloaded regions
- •Global alerts for major hurricanes, M6.5+ earthquakes, volcanic eruptions, radiation, severe space weather
- •Push notifications on mobile; alerts queue while offline and deliver on reconnect
Specialty data layers
- •National Park Service: trails, roads, boundaries, parking, wilderness areas
- •USFS and BLM trail and road systems
- •Native Hawaiian trail systems (Na Ala Hele) where available
- •Coming: USGS USMIN overlay — 700K+ mine and prospect features as an optional downloadable layer
Pins, plans, personal data
- •Drop waypoints, save destinations, plan routes, mark hazards
- •Encrypted cross-device sync — your pins follow you between devices without us seeing them in plain text
- •On-device data encrypted with a device key you control
True multi-platform
- •iOS, Android, Windows, macOS, Linux, web
- •Same account, same data, across the lot
- •Designed so a household or response team can be on a mix of devices
Privacy by design
- •Search history is not profiled
- •No ad tracking, no telemetry
- •Map tiles served locally after one download
- •Devices share data via end-to-end encryption — we cannot read your pins
Backcountry-ready. Hurricane-ready. Grid-down-ready.
Who it’s for
Anyone whose plan has to work when the cell network doesn’t.
People in disaster-prone regions
Hurricane coasts, wildfire country, earthquake zones, tornado alley, volcanic regions — anyone who has lost cell service during the event that mattered most.
Backcountry travelers
Hikers, hunters, anglers, overlanders, dispersed campers, off-roaders, backcountry skiers, splitboarders, and snowshoers — anywhere coverage drops off the highway.
Paddlers, anglers, and inland boaters
Lake fishermen, kayakers, canoeists, and recreational boaters who launch from shore and need their plan to survive a thunderstorm rolling over the trees. Launch access, river takeouts, marina locations, and severe-weather alerts — the parts of being on the water that depend on knowing the land.
RV and van-life travelers
Crossing low-coverage terrain in rigs that need routes built for them. Tell Keryx your weight, height, and length — 5th wheels included — and it avoids low bridges, weight-restricted roads, and turns you can't make.
Search & rescue, CERT, ham radio
Shared waypoint tooling that works during the outage, not just before it.
Field professionals
Utility workers, surveyors, foresters, conservation crews, archaeologists, geologists, mining engineers — operating where there is no LTE.
Privacy-conscious travelers
Journalists, researchers, and anyone who doesn't want their movements logged by a third party.
Preparedness-minded households
People with a 72-hour kit, a generator, or a Starlink — who want their map app to match that posture.
When to use Keryx
Keryx doesn’t do live traffic, transit overlays, or crowd-sourced ETAs — and won’t. Those features require tracking every user’s location in real time and aggregating it back. Your route never leaves your device; there’s no aggregate to crowd-source from. That’s the trade we made. If you need rush-hour traffic in a downtown core, use a different app for that trip. Reach for Keryx when any of these are true:
The simple test
If your plan still has to work when the cell network doesn’t, you want Keryx.
Try it
Available on iOS, Android, Windows, macOS, Linux, and the web — same account, same data, across the lot.
Visit the product site: keryxmaps.com