Help & contact

Two devices with Gruselknopf: one hidden in the room (room device) and the other as the remote. The remote can also be a web page in the browser, with no app at all (open the link from the room device or type the five-letter code). Both devices need internet, Wi-Fi or mobile data. iPhone, iPad and Android can be mixed freely.

1. On the room device choose “Connect two phones” on the start screen, set the volume and the ready time, and tap “Next”. It shows a QR code and a five-letter code.
2. On the second phone scan the QR code with the camera app. Gruselknopf opens and connects. Or in the app, under “Next”, choose “Use this phone as the remote”, allow the camera and scan the code.
3. The room device continues by itself. Tap “Done” and put the device in its place in the room.

If a device is already connected, the app asks before connecting again. The camera only reads the code. Nothing is recorded or sent.

Move a little closer and hold steady, turn up the brightness on the room device and avoid reflections. If the camera doesn’t start, allow the camera for Gruselknopf in your phone’s settings.

• Is the room device turned up and not muted? Under “Status” the remote shows volume, battery and reachability.
• Do both devices have internet? A weak Wi-Fi signal in the cellar is the most common reason.
• The silent connection test on the remote shows whether the room device is reachable. No sound plays during it.
• If nothing helps, choose “Disconnect” on the room device and connect both devices again.

You choose a time until which it stays ready. “In 2 hours” is suggested, also past midnight. After “Done” the device shows for ten seconds that it is now receiving messages, then the screen goes almost black. It is best plugged into a charger.

Android: The app asks for an exception from battery optimisation. Please allow it, otherwise the system puts the device to sleep. Battery saver mode can also slow it down.

iPhone and iPad: The app plays a silent audio track in the background to stay awake. It is better to turn off Low Power Mode.

The Watch app comes with the iPhone app. If your iPhone is the remote, you can scare right from your wrist. If it is missing on the watch, install it in the Watch app on the iPhone under “Available Apps”.

No. The app signs in anonymously, with no name, no email and no ads. Details are in the privacy policy (German).

If you delete the app from both devices, the connection can no longer be used. If you also want me to delete the stored connection and your feedback, write to me using the form (topic “Privacy”). It is quickest if you say roughly when you connected or sent feedback.