You can now simply walk through your project in the walk mode view and take measurements without having to change to the 3D view. Sphere XG will help you to enter some reference data for your measurements and then you're good to go.
The approach described below works for 360° photos without depth information. If your 360° have depth information, you can simply start measuring. The measurement will only be available in the 360° photo in which the measurement was made.
1. Go to the walkmode view of your project and navigate to the location where you want to take a measurement.
2. Click the 
icon in the toolbar on the right side.
3. Enter the Camera height from the ground to the center point of the camera lense as accurately as possible.
4. Click Next.
5. In the next three steps, pick points at both bottom corners of a wall and then at the top of the wall.
You should select 360° photos which are as vertical as possible.
You can now measure distances on this wall or between this wall and other walls. To add new walls, click Add wall in the toolbar.
Tip: Hold the SHIFT key to measure horizontal or vertical distances.