Support

Ghost Gauge for iPhone and iPad

Ghost Gauge is the companion app for the Ghost Gauge and the Ghost Gauge Nano, which plug into your car's OBD-II port. It shows the readings your car reports, keeps alarms on your Lock Screen, records rides, changes the gauge's settings, and installs new firmware.

No gauge? Turn on Demo mode in Settings › This iPhone — or wait a few seconds on the connect screen and tap Try demo mode. The app then runs against a simulated gauge so you can see everything it does.

Requirements

iPhone or iPad running iOS or iPadOS 26 or later
A Ghost Gauge or Ghost Gauge Nano, plugged into a car that answers OBD-II (most cars sold since the mid-2000s), with the ignition on

Connecting for the first time

Plug the gauge in, turn the ignition on, and keep the phone near it.
Open the app and pick your gauge from the list. Its name ends in the gauge's own four-character code, which a Ghost Gauge shows on its Telemetry screen under THIS GAUGE.
The gauge shows a six-digit code and iOS asks for it. Type it in. After that the phone is remembered and reconnects without asking.

Common problems

The app says it is looking for the gauge and never finds it

Check the gauge's Telemetry screen. If it shows Wi-Fi rather than Bluetooth, it is mid-update: it returns to Bluetooth by itself within five minutes, or you can power it off and on.
Check Bluetooth is on, and that Ghost Gauge is allowed to use it in iOS Settings › Ghost Gauge.
Don't swipe the app away in the app switcher — that stops it reconnecting on its own.

It asks for a pairing code that the gauge never shows

The gauge has probably forgotten this phone while the phone still remembers the gauge. Forget your gauge (GHOST-GAUGE- and its code) in iOS Settings › Bluetooth, then open the app and tap PAIR AGAIN.

The app says CAR NOT CONNECTED

The gauge is on and talking to your phone, but no car is answering it. Check it is pushed fully into the OBD-II port (usually under the dash by the driver's knees) and that the ignition is on — most cars only answer with it on. A reading your car doesn't report shows as --.

Settings won't save

Changes need a paired phone. If the status bar at the bottom of Settings says the gauge didn't answer, tap Retry once the gauge is back in range.

A firmware update stopped part way

Keep the app open on the update screen until it finishes. If it says it couldn't reach the gauge, check that Local Network is on for Ghost Gauge in iOS Settings › Privacy & Security › Local Network. The app puts the gauge back on Bluetooth when an update fails. If it somehow stays on Wi-Fi, the gauge gives up and returns to Bluetooth by itself after five minutes — or power it off and on. The gauge keeps running the firmware it already had; a failed update cannot leave it without one.

Rides aren't being recorded

Check the log button at the bottom of the dash says End log, which means logging is on. A ride is recorded while the engine is running; five minutes with the engine off or the gauge out of reach ends it, and rides under a minute are discarded.

On the gauge itself

Tap the right half of the panel for the next screen, the left half for the previous.
Hold the left half until the bar fills, then let go, to step the colours: dark → light → automatic. The screen tells you which one it is about to switch to, and letting go before the bar fills cancels.
Hold the right half the same way to reboot it.

Contact

Questions, problems or suggestions: Ghostgauge1@gmail.com

Please include your app version and the gauge's firmware version — both are in Settings.