Troubleshooting

Before you start

• The landing page shows how many visitor slots are in use. When all of them are taken, you can still click Start, but expect a wait of up to about 10 minutes.

• Startup takes about 5 minutes even when a slot is free. A fresh server is prepared for every visitor. Keep the tab open and in the foreground while you wait.

Messages you may see

Message	What it means	What to do
All slots are busy	Every visitor slot is in use and none freed up in time	Try again in a few minutes
AWS is out of capacity right now	The cloud provider has no free GPU servers in the region. This is on their side, not the demo's	Try again later. It usually clears within a few hours
Couldn't start a session	Something went wrong while setting up your server	Try again shortly
Demo temporarily unavailable	The demo is offline	Check back later
Session time is up	You reached the 30-minute limit	Start a new session
Session ended due to inactivity	Ten minutes passed with no input	Start a new session
Connection lost	The stream dropped and cannot be resumed	Start a new session

Black screen after "Connecting"

The app takes a few seconds to load after the stream connects. Wait a moment. If the screen is still black after a minute, end the session with the ✕ button and start a new one.

Lost connection

Sessions cannot reconnect. The most common causes are switching between Wi-Fi and mobile data, locking the phone, switching apps on a phone, or putting the computer to sleep. Start a new session when you are back on a steady connection.

No sound

Click or tap the stream once. Browsers only play sound after you interact with the page. On an iPhone, check the ring/silent switch on the side of the phone.

On a phone

• Text is small. Turn the phone sideways for a bigger view.

• Use one finger to move the view, two fingers to look around, and pinch to zoom. See Getting around.

• There is no keyboard, so Walk Mode is not available. Stay in Fly Mode.

• If the page says this in-app browser cannot play the stream, open the link in Safari or Chrome instead of inside the app you tapped it from.

Controls not responding

• Click once on the 3D view to give it focus, then try the keys again.

• If dragging stops moving the camera, press T. It toggles touch input, which is easy to press by accident.

• The Controls button at the top right lists every control.

Getting help

If something is not covered here, or the demo behaves differently than described, email [e-mail]. To help us sort it out quickly, include:

• What you were trying to do, and the steps that led to the problem

• Whether you were in Fly Mode or Walk Mode

• The active scenario, if the problem involves the buildings

• Any message shown on screen

• A screenshot or short recording, if you can

• Your device and browser

Last updated: September 9, 2026