Topo

地形 chikei

Topographic maps for the trail on an E Ink phone: contours, public land, forest roads, trails and lot lines, drawn in black and white like a paper quadrangle, and there with no signal.

Chikei is the lie of the land: the ordinary word for the shape of the ground a topo map sets out to show.

Current version: 0.2.6.

Built for the Mudita Kompakt, whose 4.3" panel has sixteen greys, a slow redraw, and is read on a ridge as often as at a desk.

Screenshots

What it shows

The map works as soon as it is installed, with nothing to set up:

• USGS topo from The National Map in the United States: the familiar quadrangle, with contours, trails, forest roads and names.
• OpenTopoMap everywhere else: a topo map drawn from OpenStreetMap, with contours and hill shading.
• Contour lines anywhere, drawn on the phone from open elevation data (the Terrain Tiles), over a faint hill shade, wherever neither map has a tile, or there is no signal. The same elevation feeds the elevation readout and a track's elevation profile.

Region packs from a server of your own, if you run one, draw over all of this and show more:

• Contours from the region's elevation model. In the US they come from 3DEP's lidar where it has it, in feet: every 40 with every 200 labelled when zoomed out, and every 20 with every 100 labelled close in, like a 20 ft USGS quad. Elsewhere they are in metres (every 20 and 100, then every 10 and 50)
• Public land as a light grey tint with its boundary: national forests, BLM land, national and state parks, wildlife areas, state trust land and local parks. Private land stays white; tribal land is outlined but not tinted, since it is not public land
• Lot lines on private land, where a state or county publishes them
• Forest roads with their numbers, and Forest Service trails by name
• Everything OpenStreetMap knows: roads, tracks, paths, water, peaks, places, and the boundaries of parks and reserves anywhere in the world

What it does

• Save this area, in the map's menu, keeps what is on the screen for use with no signal: the USGS topo map (in the US) and the elevation for contour lines (anywhere). It shows the size first; an area over 200 MB is refused, with a note to zoom in. Saved areas are listed, with their sizes, under Settings > Map > Saved areas, where a second tap deletes one. OpenTopoMap's tiles are never saved, since its rules forbid downloading for offline use; what you looked at recently may still show from the phone's cache.
• With no signal the map shows, in order: your region packs, saved areas' topo maps, saved areas' contour lines, then whatever tiles are still in the cache.
• Settings > Map > Map picks the map: Automatic (USGS in the US, OpenTopoMap elsewhere), USGS only, OpenTopoMap only, or My region packs only, which keeps the map off the network altogether.
• Download region shows the regions on the server as squares on a map: USGS 7.5-minute quadrangles in the US, and elsewhere 1/8-degree squares named after the largest place in each. Tap the squares you need; each comes with its own elevation, and neighbours join without a seam.
• Here, on the map: mark where you are standing, or start and stop recording your track.
• Hold a finger on the map to see whose land it is, as far as the region's records go: the park, forest or reserve and who holds and manages it; the owner of record of a private lot; a conservation easement and its holder; wilderness and other designations laid over it; and whether the public may enter. Where nothing is recorded it says so. Beneath that, how steep the ground is, which way it faces, and its UTM coordinate.
• Track detail sets how closely a recording follows you: a point a minute, or every 30, 10 or 5 seconds.
• Call for help from here: with Field Kit installed, the last item under Here opens Field Kit's "Calling for help" page with your position on it, ready to read out or send.
• Share GPX hands a recorded track to CalTopo, or to anything else that takes GPX.
• Open a GPX file from Cabinet or an attachment, and Topo offers its paths to import; a file of waypoints alone becomes beacons.
• Forage, a layer added from the map's Layers > Additional layers, shows fruit and nut trees and shrubs nearby: trees and shrubs from OpenStreetMap, and, in builds with a Falling Fruit key, the spots on Falling Fruit, the open map of edible plants. Both go through one list of plants grown or foraged for their fruit, berries or nuts (apples, plums, mulberries, walnuts, hazels, brambles and so on), so city maps are not crowded with the maples, oaks and lindens Falling Fruit also counts. Tap one for its name, season and access notes where they are known, and where the record comes from. Where the two sources hold the same tree it shows once, with Falling Fruit's notes. Zoomed out, Falling Fruit's counts stand in for the spots. What it fetched is kept for a month, so the layer works with no signal where you have already looked, and Save this area keeps the area's spots too. Mushrooms are never shown: Topo does not say what is safe to eat. Check before you pick: some spots are on private land or gone.
• Streets, a layer added the same way, draws every street and path cut into pieces of about 25 m: thin black where none of your tracks has been along it, thick where one has, and a line just below the middle of the screen with the share of the streets on screen you have walked. It counts every recorded track and imported GPX in Paths; a straight run between two fixes counts as walked, but a pause of more than two minutes between fixes does not. Streets come from OpenStreetMap once per place and are kept, so the layer works with no signal, and Save this area keeps the area's streets too. The walked part is worked out on the phone.
• Navigate to a marked place, with distance, bearing and elevation.
• User guides (hold a finger on a tool): their text can be selected and a word sent to a dictionary app such as Define, which waits behind a ⋮ on the selection bar.

What it needs

• Location, to put you on the map and record tracks. It stays on the phone.
• Internet, only to fetch map tiles and elevation, while the map is open or when you save an area; fruit and nut trees for the area on screen, while the Forage layer is on; streets for the area on screen, while the Streets layer is on; and region packs from a server you set, when you ask. See PRIVACY.md.
• A map server of your own: optional. Region packs add public land, lot lines and forest roads offline. They are plain files built by the scripts in mapdata/ from public data and served by anything that serves files: tailscale serve, nginx, a folder on a web host. Offline Maps > + > Download region asks for the server's address.

What it does not do

• It does not route. It shows the ground, and you choose the way.
• It does not replace a paper map and a compass.
• It does not send your location anywhere. There is no account and no analytics.

On a Mudita Kompakt

DuraSpeed, a MediaTek service on the Kompakt, closes installed apps a few minutes after the screen goes dark and keeps them closed until they are opened again. For Topo that means a track recorded with the screen off can stop partway. Mudita's own apps are on its allow list; this one has to be added, once.

Kompakt's Settings has no way in to DuraSpeed: no menu entry, and no search box to look for it in. Its own screen will not open for another app either, but its App info page will. Messaging and Whereabouts each have a button that goes there; without either, from a computer with adb:

adb shell am start -a android.settings.APPLICATION_DETAILS_SETTINGS -d package:com.mediatek.duraspeed

Then, on the phone:

1. Tap Open on DuraSpeed's App info page.
2. Switch Topo on in the list. On means allowed to run in the background, which is easy to read the wrong way round. Switching DuraSpeed off at the top works too, for every app.

Getting it, and keeping it

Download https://github.com/wanderwildwood/chikei/releases/latest/download/chikei.apk and sideload it. That address always points at the newest release, and every release publishes a .sha256 beside the APK if you would rather check than trust.

For updates without doing this by hand, add this repository to Obtainium:

https://github.com/wanderwildwood/chikei

The application id is settled: updates install over what you have, keeping your maps, tracks and marks.

Building

./gradlew assembleRelease

A release is signed by a keystore in signing/, which is not in this repository. Without it the release APK builds unsigned and will not install anywhere; there is no fallback key by design.

Building regions

mapdata/fetch.py <west> <south> <east> <north> <area> [--sources a,b,...]   # data for an area
mapdata/build_cells.py <area> <cells>                                       # one pack per cell
mapdata/publish.py <site> <cells>/*/                                        # a static site with packs.json

They need Python 3 with numpy, shapely, rasterio and contourpy, and osmosis with the Mapsforge map writer plugin. Nothing needs an account or a key.

Each kind of data is a source. An area in the United States takes the US sources, and anywhere else takes the world ones; --sources picks your own.

Source	Where	What it adds
usfs	US	national forests' own ownership, roads and trails (USDA Forest Service)
padus	US	all public and protected land, with owner, manager, easements, wilderness and other designations, and public access (USGS PAD-US)
tribal	US	reservations, off-reservation trust land and Hawaiian home lands (Census TIGER)
parcels	US	county lots with the owner of record, from each service listed in PARCELS in fetch.py whose area meets yours
wdpa	world	national parks, reserves and other protected areas, with their designation and managing body (Protected Planet)
quads / grid	US / world	how the area is cut into packs
osm	both	OpenStreetMap, from the smallest Geofabrik extracts that cover the area
dem	both	elevation: USGS 3DEP 10 m in the US, Copernicus GLO-30 elsewhere

Parcels are published county by county and state by state, and many do not publish owners at all. North Carolina's statewide service is listed; to add your own county, put its ArcGIS parcel layer, the name of the field holding the owner, and its bounds in PARCELS. Only the outline and the owner are ever fetched: never mailing addresses or values.

Terms. PAD-US, TIGER, 3DEP and the Forest Service's data are public domain; OpenStreetMap is ODbL. Copernicus DEM is free to use with its credit, which each pack carries. WDPA is free for personal and non-commercial use; before serving packs built with it to the public, read its terms.

Each pack is three files: the Mapsforge map, the elevation, and a small land file saying whose land each part of the cell is (see mapdata/land_pack.py). The app knows nothing of any one country's agencies; it says what the land file says.

Credit

Maps with no setup: USGS The National Map (public domain; "Map services and data available from U.S. Geological Survey, National Geospatial Program"). OpenTopoMap (CC-BY-SA): map data © OpenStreetMap contributors, SRTM; map style © OpenTopoMap. Terrain Tiles by Mapzen, on the AWS Registry of Open Data, with their sources credited as their documentation asks: 3DEP (formerly NED), GMTED2010 and SRTM courtesy of the U.S. Geological Survey; ETOPO1, U.S. National Oceanic and Atmospheric Administration; EU-DEM, produced using Copernicus data and information funded by the European Union; ArcticDEM, created from DigitalGlobe, Inc. imagery and funded under National Science Foundation awards 1043681, 1559691 and 1542736; © Commonwealth of Australia (Geoscience Australia) 2017; Canada, contains information licensed under the Open Government Licence – Canada; Mexico, INEGI, Continental relief, 2016; New Zealand, Crown copyright Land Information New Zealand and the New Zealand Government; Norway, © Kartverket; United Kingdom, © Environment Agency copyright and/or database right 2015; Austria, © offene Daten Österreichs – Digitales Geländemodell (DGM) Österreich. The outline of the US that picks between USGS and OpenTopoMap is from Natural Earth (public domain).

Forage: trees from © OpenStreetMap contributors (ODbL), through the Overpass API, or, when that server is busy, the public instance run by Private.coffee. Edible plant locations from Falling Fruit and its sources, under each dataset's licence (mostly ODbL).

After Trail Sense by Kyle Corry, which this is: its sensors, paths, beacons, navigation and Mapsforge rendering are Trail Sense's, cut down to the map and what you do with it. Trail Sense is under the MIT License, kept in LICENSES/MIT-Trail-Sense.txt.

Map data © OpenStreetMap contributors (ODbL). In the US: public and protected land from USGS PAD-US, national forests, forest roads and trails from the USDA Forest Service, tribal land from the US Census Bureau, elevation and quadrangles from the USGS, and parcels from the states and counties that publish them. Elsewhere: protected areas from UNEP-WCMC and IUCN, Protected Planet (WDPA), and elevation from Copernicus DEM GLO-30, © DLR e.V. 2010-2014 and © Airbus Defence and Space GmbH 2014-2018, provided under COPERNICUS by the European Union and ESA.

Licence

GPL-3.0-only. See LICENSE.

Copyright (C) 2026 wander wildwood

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 3.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.

A map you carry into the woods should stay free to fix and share, so the changes made here are copyleft. Trail Sense's own code keeps its MIT licence.