Antinode listens through the microphone, so it needs permission and it needs to be able to hear the room. Check Settings → Antinode → Microphone. If the picture moves but only slightly, raise the Mic slider in the panel: a phone across the room from a speaker hears about a hundred times less than one beside it.
Open Control Center, tap Screen Mirroring, and choose your Apple TV. Antinode then takes the screen for itself — full width, no interface — and the phone stays the desk. iOS does not let any app start mirroring on your behalf, which is why this is a manual step.
Every world is solved for every pixel, and a few of them are expensive. The Quality slider trades resolution for speed, and the app also lowers its own detail when a world will not fit the frame. A hot phone renders more slowly; that is the hardware protecting itself, and it recovers when the device cools.
Open Antinode Plus from the ··· menu and tap Restore. Purchases are tied to your Apple Account, so this works on any device signed in to the same account.
The flash limiter is on by default when the system's Reduce Motion setting is on, and can be switched from the ··· menu at any time.
hello@magiscan.com — please say which device and which iOS version, and what the app was doing at the time.