What the source shows
The author account describes building a playable mobile AR experience and reaching TestFlight. Camera, gyroscope and rendering behavior had to work together on a device.
Supporting documentation (opens in a new tab)What to take into your own work
Use the first playable loop as a checkpoint: find a ghost, interact, receive feedback and repeat. Device motion, performance and production builds need their own checks after the scene looks convincing.
What this does not establish
The source describes differences between development and production behavior. Timing and success are author/vendor reports, not a recipe we have reproduced.