Maps go blank
Map apps stream tiles from the internet. Without a connection you get a gray screen, and the same is true for the phone's navigation and search.
Offline maps · On-device AI · iOS & Android
When the grid goes down, your phone still works.
GridDown puts offline maps with 4.4 million survival points of interest and an AI assistant trained on 40+ field guides on your phone. No signal, no cloud, no server that can go dark. Set it up once and you're ready.
- Runs entirely on your phone
- No account required
- One email at launch, nothing else
Why you need it
Everything on your phone assumes the internet.
The moment the power goes out for longer than a few hours, the tools you rely on quietly stop working. GridDown is built for exactly that moment, whether the cause is a storm, a grid failure, or something worse.
Answers go dark
"How do I purify water?" is a question you Google. Every AI assistant on the market needs a server on the other end. When it's gone, so is the answer.
Signal fades
Cell towers switch to backup batteries once the grid fails. Most have hours of reserve, not days. After that, your phone is only as useful as what's already on it.
Hours
Lights, refrigeration, and internet at home are out. Cell service degrades as tower batteries drain.
Days
Gas pumps, ATMs, and card readers are down. Water pressure drops in systems that depend on electric pumps.
Weeks
Supply chains stall. Decisions about water, heat, sanitation, and whether to stay or go become daily and serious.
Months
It has happened. After Hurricane Maria in 2017, parts of Puerto Rico waited close to a year for power to come back.
What's inside
Two things that keep working when nothing else does.
An AI assistant that runs on the phone's own processor, and a map that works the same whether you have five bars or none.
On-device AI
Ask it anything. It answers from the phone, not the cloud.
Works like the AI chat apps you already use, with saved chats, memory, personalization, and tone settings. Except it keeps working in airplane mode.
Offline mapsDownload your region. Navigate without a tower in sight.
Routes, bookmarks, search, and toggleable survival overlays over a map that's stored on the phone. Switches between online and offline on its own.
On-device AI
A survival expert in your pocket. No connection required.
GridDown runs a language model directly on your phone. It's fine-tuned on survival and disaster-preparedness material and answers from a built-in knowledge base of 40+ field guides, with steps, warnings, and the source it pulled from.
- Saved and archived chats, so answers you've already found stay findable
- Basic memory and personalization: your name, medical notes, family details
- Tone and style settings for how it talks to you
- Four model tiers, from Standard (fast) to Expert (reasoning). Pick what your phone can handle
- Asks clarifying questions about your situation before giving advice
How do I filter water without any tools?
How do I treat hypothermia with no medical help?
Is it safe to run a generator in the garage?
How long does canned food stay good?
How long will fuel stay good in an unused car?
Do vet clinics carry antibiotics?
What GMRS channel should my family use?
Which wild berries are poisonous?
Real answers, captured in airplane mode
Built like the chat apps you already know
Offline maps
One map. Works online, works offline, switches on its own.
With a connection you get three live base maps: Outdoor, Topo, and Streets. Lose the connection and GridDown drops to the survival-optimized map stored on your phone without missing a beat. Every overlay, bookmark, and saved route works in both modes, even when coverage is spotty.
- Download by country and state, at the detail level your storage allows
- 3D terrain overlay with hillshading and elevation
- Compass, GPS and MGRS coordinates, scale bar, and zoom, each toggleable
- Search by address, landmark, city, intersection, brand, category, or raw GPS and MGRS coordinates
- Location intel: survival notes for the terrain you're standing on
Map overlays
Maps that show what matters in an emergency.
Standard maps show you coffee shops. GridDown's downloadable overlays show water, fuel, medical supplies, escape routes, and the infrastructure around you. Toggle each one on or off as you need it.
Survival POI database
Nine categories of places you'd actually need, searchable offline and toggleable one at a time.
Landmarks & navigation
Built in, no download needed. Bridges, tunnels, dams, mountain passes, peaks, airfields, military sites, and more.
Hiking trails
Off-road escape routes: hiking paths, bridleways, and foot tracks for moving through wilderness when roads are blocked.
Vehicle trails
4x4 tracks, fire roads, and drivable trails so you have options when highways are jammed or closed.
Infrastructure
High-voltage lines, substations, backup generator clusters, railways, and pipelines. Available as a smaller power-grid-only download too.
Land use
Wetlands, quarries, landfills, and industrial zones, so you can route around hazards and read the terrain ahead.
3D terrain
Hillshading and elevation on the base map, so ridgelines, valleys, and drainages are obvious at a glance.
The database
4.4 million places that matter when the grid is down.
The Survival POI database is built from Overture's open map data and filtered to 225 categories you'd need in a crisis, covering the entire United States. It lives on your phone and searches instantly with no connection.
4.48Msurvival points of interest
225curated categories
1.29Mwater resources
411Kmedical facilities & pharmacies
171Kemergency services
257Kfuel & propane sources
446Kfood sources
467Krepair & hardware
Plus a built-in base that ships with the app.
Even before you download anything, GridDown includes a half-million-entry database of the places and terrain that define a region: the sites that will be defended, the fields where aircraft can land, the water you can walk to, and the passes you'd have to cross.
Security & military
- 5,960 defense facilities
- 4,582 armories
- 4,559 military bases
- 1,179 training ranges
- 750 Coast Guard stations
- 488 fortifications
- 72 military airfields, 22 naval bases
Airfields & ports
- 15,289 small airports & landing strips
- 8,179 heliports
- 912 medium & large airports
- 673 seaplane bases
- 3,493 channels, 13,741 bays
Terrain & infrastructure
- 8,416 mountain passes
- 69,633 peaks, 14,797 ridges
- 7,141 bridges, 452 dams, 123 tunnels
- 17,889 islands, 4,548 cliffs
- 21,756 cities and capitals
Water & public land
- 72,841 reservoirs, 70,239 lakes
- 36,399 springs, 873 hot springs
- 3,802 rivers, 2,559 waterfalls
- 62 national parks, 114 national forests
- 5,327 nature reserves, 1,326 state parks
Routes & bookmarks
Plan the way out before you need it.
Pick two points and GridDown gives you three routes: by road, by ATV and bike trails, and on foot by hiking paths. Save the ones that matter and they stay on your phone, ready to open with no signal at all.
Primary (roads)44.8 mi · 1 h
ATV / bike (trails)48.8 mi · 4 h 2 m
Hiking / walking (paths)52.1 mi · 17 h 23 m
Example from the screenshots: one home-to-cabin trip, three ways to make it.
- Bookmark home, family, and fallback locations in advance
- Quick access to saved places and recent searches
- Route paths render on the offline map, no turn-by-turn voice needed
Downloads & storage
You decide what to carry.
Every map, database, and AI model is a separate download with its size shown up front. Load a little or a lot, and audit what's on the phone any time.
Maps
| World baseline map | 516 MB |
| U.S. baseline map | 1.9 GB |
| U.S. 3D terrain | 1.4 GB |
| State map (e.g. Colorado) | 532 MB |
Databases
| Built-in landmarks & navigation | 768 MB, included |
| Survival POI database | 1.41 GB |
| Hiking trails | 2.77 GB |
| Vehicle trails | 3.93 GB |
| Infrastructure | 1.32 GB |
| Power grid only (stand-alone) | 395 MB |
| Land use | 1.65 GB |
AI models
| Standard (fast) | 0.75 GB |
| Enhanced (accurate) | 1.88 GB |
| Advanced (smart) | 2.62 GB |
| Expert (reasoning) | 4.07 GB |
Knowledge base
40+ field guides. Written for the day you need them.
Each guide is researched from CDC, EPA, FEMA, USGS, and military field manuals, written for a stressed non-expert, and baked into the on-device AI. Browse them, or just ask.
Start here
- System failures: what breaks, in what order, and how to prepare
- Emergency planning, checklists & records
- Shelter-in-place planning
- Evacuation planning & routes
Core survival
- Water: sources, treatment & storage
- Firecraft: starting, use & safety
- Basic shelters & protection
- Navigation & map reading
- Dangerous wildlife encounters
Food
- Food safety, cooking & preservation
- Food procurement: fishing, trapping & hunting
- Foraging & wild edibles
- Food production: gardens & small livestock
Medical
- Basic first aid
- Intermediate first aid
- Medical & rescue: triage and evacuation
- Medicines & pharmaceuticals
- Herbs & medicinal plants
- Childbirth in low-resource settings
- Dentistry basics
Health & sanitation
- Sanitation, hygiene & waste
- Public health & infection control
- Cold weather, indoor heat & CO safety
- Extreme heat & smoke safety
Energy & utilities
- Fuel & combustible energy
- Power & generators
- Electrical basics
- Water systems: collection, pumps & distribution
Hazards
- Hazmat & chemical safety
- Radiation & fallout safety
- Home safety, damage & cleanup
Communications
- Radio types: two-way, CB, GMRS, HAM
- Protocols & common frequencies
- Emergency monitoring
- Signaling & Morse code basics
Repair & fabrication
- Tools & materials: repair, sharpening & salvage
- Engine & small equipment basics
- Metalworking basics
- Basic carpentry & woodworking
- Mobility: bikes, carts & transport
Security & community
- Firearms & ammunition basics
- Community ops: security, de-escalation & mutual aid
- Psychological resilience & group stability
How it works
Set it up on a normal day. Forget about it until you need it.
- 1
Install the app
iOS or Android. No account, no sign-in, no subscription servers between you and your data.
- 2
Download your maps, databases, and AI
Pick your country and state maps, the overlays you want, and the model your phone can run. Do it once while you still have Wi-Fi.
- 3
Turn on airplane mode. Everything still works.
Maps, routes, overlays, guides, and the assistant all run from the phone. Keep a power bank nearby and you're set for the long haul.
FAQ
Questions people ask.
Is it really completely offline?
Yes. Once your maps, databases, and AI model are downloaded, GridDown makes no network requests. The map tiles, the search index, the guides, and the language model all live on the phone. Every screenshot on this page was taken in airplane mode.
What happens if I'm online?
You get live Outdoor, Topo, and Streets base maps and online search on top of everything else. The moment the connection drops, the app falls back to its offline map and keeps going. Overlays, bookmarks, and routes behave identically either way.
What phone do I need?
A recent iPhone or Android phone. The on-device AI is the most demanding part, which is why there are four model sizes from 0.75 GB to about 4 GB. Older phones run the Standard model; newer ones can run Expert. Exact requirements will be published at launch.
How much storage does it take?
You choose. A minimal setup (U.S. baseline map, one state, the Survival POI database, and the Standard model) is about 5 GB on top of the app. Everything, including every trail and infrastructure layer and the Expert model, is about 20 GB. Every download shows its size before it starts, and the app audits its own storage.
Does the AI replace real training?
No. It's a knowledgeable reference that is available when nothing else is. It cites the guide it pulled from so you can read the full context, and it flags the situations where you need a professional or should not attempt something yourself.
Does the map cover my area?
The initial release covers the United States, with a world baseline map and state-level detail you download individually. The POI database is nationwide.
What will it cost, and when does it launch?
Pricing isn't final. Our goal is a one-time purchase with no subscription, because a subscription that needs a server defeats the point. Waitlist members hear first and get the launch price.
Be ready before you have to be.
Join the waitlist and we'll email you once, when GridDown launches on iOS and Android. No newsletters, no drip campaigns.
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