GPSLarpHelp

GPSLarp is asking for my Mac's administrator password

A macOS password dialog appears the first time you try to do anything with your iPhone, and you would reasonably like to know what it is for before typing anything into it.

It starts the connection between the Mac and the iPhone. macOS restricts that connection to administrators, so it raises its own dialog — GPSLarp does not draw it, does not read what you type, and never receives your password.

01What the prompt is actually starting

GPSLarp does not talk to the iPhone directly from the app window. It opens a connection over Apple's device-development protocol — the same one Xcode uses — and that connection needs a low-level network interface on the Mac that macOS only lets administrators create. Hence one password, once, before any phone is visible.

Three things follow from that, and each is the answer to a question people reasonably ask before typing a password into anything:

02When you should and should not see it

01Once per session, and only if the connection is not already up

If the connection is already running when GPSLarp looks — because you have used it since the Mac last restarted — there is nothing to start and no prompt.

02Never before you have signed in

The app checks who you are before it goes anywhere near this prompt. That order is on purpose: being asked for an administrator password and then being told you cannot use the thing it started is the wrong way round, so a signed-out user is never shown it at all. If you are seeing a sign-in screen instead of this prompt, that is why — sign-in trouble is the page.

03Not from a standard account, unless you know an administrator's password

macOS will accept an administrator's name and password typed into the prompt even when the account you are logged into is a standard one. What it will not accept is a standard account's own credentials.

03What happens if you dismiss it

Nothing bad, and nothing useful. The connection does not start, so no iPhone can be found — whether or not one is plugged in. The app says it could not start the connection, which is a different message from the one you get when the connection is running and no phone is behind it.

That distinction is the whole diagnostic. If you are looking at "the connection could not be started", the prompt is the thing to fix. If you are looking at "no iPhone detected", the connection is fine and the problem is on the iPhone side.

To be asked again: quit GPSLarp and reopen it, then try to reach the phone. There is no separate button for retrying the prompt.