GPSLarpHelp

How do I set an exact latitude and longitude?

You have a spot in mind — a coordinate pair from somewhere else, or a point you can see on a map — and you want that exact position rather than roughly the right city.

There are three ways to choose a place: click the map, search by name or address, or pick one you saved earlier. Decimal degrees is the form to type. And the thing nobody tells you: GPSLarp has no coordinate field and parses no coordinates itself, so a typed pair can fail to resolve where a click on the map cannot.

01Three ways to choose a place

Clicking the map does one extra thing quietly. Having placed the pin, it asks a naming service what that point is called, in the background. If that lookup fails, the pin is named with its raw coordinates instead. Nothing is lost either way — the position is the position, and the name is only a label.

Screenshot pending — GPSLarp's map with a pin dropped by clicking
Clicking the map is the path that involves no interpretation of anything you typed.

02What happens when you type a coordinate pair

This is the part worth reading properly, because it is not what the interface implies.

GPSLarp does no coordinate parsing. There is no field labelled latitude, no field labelled longitude, and no format the application itself understands. The search box hands whatever you type, as free text, to OpenStreetMap's Nominatim geocoder. A decimal pair like 48.8584, 2.2945 usually comes back with the right point — but that is Nominatim interpreting it, not GPSLarp reading it.

The app's own wording gives this away, if you have seen it: when a search matches nothing it says No place matched that. Try a city, a landmark, or “48.8584, 2.2945”. It is suggesting a string to search for, which is exactly what it is.

Two practical consequences follow, and they are the reason this page exists:

Degrees, minutes and seconds

Convert to decimal degrees first, then search for that. Degrees, plus minutes divided by 60, plus seconds divided by 3600 — so 48° 51′ 30″ N is 48 + 51/60 + 30/3600, which is 48.8583. Keep four or five decimal places; that is metres rather than streets.

A hemisphere letter becomes a sign: S and W are negative.

03Setting the place

01Open GPSLarp and select your iPhone

The place has to have somewhere to go. If the phone is not in the device list, that is the thing to fix first — GPSLarp can't find my iPhone.

02Choose the point

Click it on the map, or search for it, or take it from your saved locations. All three end in the same state: a pin on the map at the coordinates that will be sent.

03If you are working from a coordinate pair, type it as decimal degrees

Into the search box, comma-separated, latitude first. If it resolves, the pin lands where you meant.

04If it does not resolve, click the map instead

Zoom in far enough that the click is precise, then click. There is nothing to reformat and nothing to retry — this path does not consult a geocoder at all.

05Set it

Confirming sends those coordinates to the phone over the connection GPSLarp is holding. This is teleport: one message rather than a journey — the app sends the new position, not a path to it, so there is nothing in between for anything to read. What the phone does with it is where this page stops; see the location didn't change for how to check on the phone itself.

Screenshot pending — GPSLarp with a place chosen, ready to set
Teleport is one jump, not a journey. If you want the position to move along a road, that is a different mode.

04What this mode does not do

It does not travel. A point on another continent is sent directly, with nothing in between — no intermediate positions and no time spent covering the distance. If you want a position that moves along real streets, use walking or driving a route, or push it around by hand with the joystick.

Search does not work offline. The app says so itself: search uses OpenStreetMap's Nominatim, so it needs the internet. Clicking the map needs the internet too, for the map tiles. What that leaves you with on a dead connection is on using GPSLarp without an internet connection.

It does not hold after the connection ends. The override exists only while GPSLarp is running and connected to the phone — which is also the easiest way to undo it, covered on putting the real location back.