One tap
Capture the place, not just the moment
A single tap grabs your GPS fix, elevation, accuracy, speed, and heading — then quietly enriches it with the place name, your timezone, and the weather right where you stood.
Offline location journal
I got lost in the desert.
After I found my way home, I made
an offline map app.
Free on iPhone GPS works without bars · real GeoJSON
Why it exists
One wrong turn off the trail and the desert all looks the same. Jumping cholla in my hand, zero bars, and Apple Maps and Google Maps — the apps everyone trusts — had nothing for me. I found my way out, then built GeoJSONic for exactly those places: no signal, thin map coverage, ground under your feet that still needs to be captured and kept.
What it is
Built for where the bars die. And the big map apps give up.
Capture a note with no cell service. GPS still works. The map underneath is Mapbox — often denser trail and rural coverage than Apple Maps or Google Maps in the places that actually matter off-grid.
Every note lives on your phone as real GeoJSON. No account, no cloud. Share a trip by handing someone a PDF — that's the Sneakernet.
The 3D globe is free. Offline map downloads, satellite, and field measurement tools are Pro.
The app
GPS doesn't need bars.
How it works
Capture. Share. See.
01 · Capture
Tap once. Keep everything.
Capture exactly where you stand — or bring a place in: drop a photo onto the map at the spot it was taken, or share a location straight from Apple Maps into GeoJSONic.
GPS 36.86915, −94.37191
Elevation 312.7 m
Accuracy ±4.9 m
Heading 271° W
Place Neosho, MO
Weather 14.2°C · Partly Cloudy
No signal? No problem.
Built for where the map runs out.
Most journaling apps quietly assume you're online — they stall, spin on a sync, or drop what you wrote the moment the bars disappear. GeoJSONic is built the other way around: capturing a note never needs a connection — your words, GPS fix, and elevation are saved on the spot, anywhere on Earth.
01
GPS without a tower
Positioning is satellite-based — no cell tower, no Wi-Fi, not a single bar. Your exact coordinates and elevation are captured deep in the backcountry, on a plane, or abroad with data switched off.
02
Saved on the spot
Every note is written straight to your device the instant you tap. No spinner, no upload queue, no account to log into. Nothing waits on a connection, and nothing can be lost to one.
03
Graceful when connected
The two online touches — the weather and the place name — fill in when you have signal and quietly sit out when you don't. The note saves cleanly either way.
RFC 7946
Every note is real GeoJSON
Notes are stored as honest GeoJSON Features on disk — not a proprietary blob. Import and export losslessly. Open them in any GIS tool. Your journal is yours to keep.
Write freely
Markdown, tags, and photos
Write in Markdown, file with tags, attach photos, video, and audio. Location is always optional — a note made with GPS off still saves, geometry simply null. Nothing is ever lost.
More than a pin
Map a whole place, not just a point.
A point is only the start. Record a route for whatever you're doing — run, walk, hike, bike, drive, or paddle — and your path draws itself as one note. Or map an area — a hunt, a scout, a survey, a round of golf, even mowing the yard — and GeoJSONic traces the perimeter, measures the acreage, and pins photos, audio, and notes exactly where you stood.
01
Routes & perimeters
Walk it and it's captured — a clean GeoJSON LineString or Polygon, carrying the metadata and media that make it a memory, not just a trace.
02
Measured on site
Every line shows its length from GPS — and you can type the real number you measured on the ground, which becomes the one that counts.
03
A PDF you can hand over
Export a scout as a clean one-page report — the map, your pins and measured lines, and a QR code back to the work. Built for the field.
Also from me
PortaDrive is on the Mac App Store.
A PDF that behaves like a drive. Drop one on PortaDrive, work with the files in Finder, eject to save. $8, no subscription.
No lock-in
This is what a note is.
Not an export. Not an approximation. The file on disk is a GeoJSON
Feature, with your words and the sensor reading of the moment living side
by side in properties. Back up your whole journal as a single .geojson file anytime.
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [-94.37191, 36.86915, 312.7]
},
"properties": {
"title": "Big Spring Park",
"date": "2026-04-18T07:52:11Z",
"placeName": "Neosho, MO",
"timeZone": "America/Chicago",
"weather": { "condition": "Partly Cloudy", "temperatureC": 14.2 },
"elevation": 312.7,
"horizontalAccuracy": 4.9,
"course": 271.0,
"tags": ["park", "morning", "spring"]
}
}02 · Share
The GeoJSONic Sneakernet.
A note bundles into a single self-contained PDF — a field report anyone can read, with the GeoJSON and every photo, video, and audio clip embedded inside. Hand it to someone the way you'd hand them anything: AirDrop, a text, an email. They open it in GeoJSONic and your trip drops onto the same globe they keep their own memories on.
New to the word? Read up on the sneakernet →Your memories travel because a person chose to hand them to another person, not because a server decided to show them.
03 · See
Your whole life on a globe.
The free 3D globe runs on Mapbox — wherever they have coverage, so do you. Open the app and you're already on the map at where you stand. Fly from any note to the exact spot it was written. Every trip becomes a story you follow stop by stop.
Tiles cache as you explore. Pro offline downloads are for guaranteeing the map when you have zero signal — download the area before you go, plus satellite basemap and on-map measurement tools for real field work.
Why no one will copy it
No incumbent can build this. Facebook, Strava, Google — their business models require the backend: the feed, the ads, the lock-in. An offline social network generates zero ad inventory and zero lock-in. Only someone with nothing to protect could build it.
Anyone can build a Sneakernet client. There's only one GeoJSONic.
Field Notes
From the person building it.
-
A little app, a growing world: GeoJSONic has reached 25 countries and regions
GeoJSONic has reached 25 countries and regions. A personal thank-you from independent developer Jason Dittmer, with version 1.3 on the way.
Read → -
Share is a PDF
In the next update, sharing a note gives you one file that's two things at once — a beautiful field report anyone can read, and a lossless, importable copy of the note itself. Here's the idea behind it.
Read → -
No cloud, on purpose
Every other app in this category is a front-end for a database you'll never see. GeoJSONic doesn't have one, and never will. That's not a missing feature — it's the whole design.
Read →
Roadmap
Now Capture-first journaling on a free 3D globe — notes, routes, and mapped areas for every activity, share as PDF or GeoJSON, lock-screen capture, and a compass that guides you back to any pin. Pro adds offline map downloads, satellite imagery, and the measurement workflow.
Next A one-tap mark-where-I-parked and spoken interval cues while you record — find your places again and know your splits without looking. Plus import from GPX, KML, and Garmin.
Later See your notes in the real world through AR, gather several shapes into one rich note, and subscribe to curated public data layers.
Pricing
Free
$0forever
Full journal, free Mapbox 3D globe, routes, areas, and Sneakernet sharing. Everything stays on your device.
GeoJSONic Pro
$3.99/ month
First month free · or $39 / year
Download whole areas for offline use before you lose signal, satellite basemap, and measurement tools for real field work.