Marchstone: Bounds & Marks

Draw: tap each corner of the area on a satellite map.
Walk: or go round it on foot and drop a corner where you stand.
Import: KML, GPX or GeoJSON, from Google Earth, a handheld GPS or farm software.

Then Track, and the phone tells you whether you are in, out, or on the edge.

Border width

1102030

How far either side of the boundary line counts as on the border. Phone GPS is usually good to 3–8 m, so anything under about 4 m will flicker between states.

Hear the warnings

Try each one now, at the volume you will be working at.

Position quality

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A phone with no satellite lock hands back a guess from wifi and phone masts and calls it a position. Those are the readings that drop you a street away. Whatever this is set to, if nothing better arrives for fifteen seconds the app shows what it has and says how rough it is.

If positions are poor everywhere, look at the phone before this app. Android gives browsers approximate location unless you grant the precise kind, in Settings, Apps, your browser, Permissions, Location.

Browsers differ as well. On Android, Chrome asks for a fused position, GPS blended with wifi, cell and the motion sensors. Firefox reads the raw GPS provider instead, so it wanders more and reports less often. Track in Chrome where you can.

Screen

Auto follows the phone. In direct sun the day setting is easier to read, because a dark screen turns into a mirror.

Keep the screen on while tracking Warnings are unreliable once the phone sleeps. Start muted Colour only: no sound, no vibration.

Your areas

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Browser storage is not a safe place to keep the only copy of anything. A backup is one file holding every area, and it reads back into any browser, phone or computer.

Offline maps

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Areas and tracking need no signal at all. The map picture does, unless you save it first with Save map while drawing.

What this app keeps on your phone

Your areas: Every boundary and the marks on it. Kept until you delete them.
Your settings: Border width, position quality, screen, sound. Kept until you clear this site's data.
Two notices: A note of the gauge explanation and the browser warning, so neither shows up twice.
The app itself: Held so it opens with no signal. Replaced whenever a new version arrives.
Saved map tiles: The imagery you asked for, up to 6,000 squares, oldest dropped first. Clear saved map tiles above removes them.

None of it is sent anywhere, and nothing here is used to recognise you. To remove the lot, uninstall the app or clear this site's data in your browser settings.

Your areas and your positions never leave this phone: no account, no analytics, nothing uploaded. Two things do reach a server. The page itself is served by its host, the way any web page is. And while the map is loading, the squares of ground you are looking at are requested from Esri or OpenStreetMap. Save the map for offline use, or work on a saved area with no signal, and the second one stops too.

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