When navigating the model with the desktop app, you can easily switch between Walk and Fly mode. Walking is required to place cameras and 360 hotspots, but flying will allow you to go through walls, doors and other surfaces. It's a great way to travel through floors or to get a view of the model from a different perspective.
Fly mode is very easy to activate once you're in the scene editor. You can use the icons or simply press spacebar to switch between the two modes. If you need to go through a door or a wall, you can press spacebar, go through and then press spacebar again. You can press "Shift" to fly and walk faster.
To fly even faster, increase your speed with the bluetooth controller. Once you are in a good position, you can add cameras to go back to later.