MallesVR: Walk through it before it's built.

Brochures and floor plans ask buyers to imagine a space. The idea behind MallesVR was to put them inside it instead, whether at a sales office, at an expo or at home, without an expensive headset.

Google Cardboard made that possible in 2016: any Android phone, a fold-up viewer and an app. The app had to be simple enough for someone who had never tried VR, with nothing to learn.

The whole experience is designed for someone holding a Cardboard to their face for the first time. A centre dot shows where you are looking. Look at a button and the dot grows into a ring that fills over two seconds, so you always know what is about to happen and can look away to cancel.

Inside a tour the controls sit on the floor below you. They stay out of the view while you look around the room, and appear the moment you look down.

MallesVR is a Unity app with three scenes. The menu loads either tour, and each tour plays its 360° video on the inside of a sphere around the viewer's head. Google's VR SDK handles head tracking, the two-eye render and the lens correction, and turns gaze into button presses.

Both tours ship inside the app, so a demo never depends on an internet connection.

First-time VR users feel lost or queasy quickly. These choices kept the experience calm.