According to a report from Wired who broke it down, this involves collecting media from your device, which we can only assume will be videos and photos, as well as your contacts. “With your permission, we may collect information stored on your mobile device, such as contacts, photos, or media files.”
As Wired points out it is unclear as to why the company would need such information from you in the first place. Another part of the policy reads that it wants to collect information such as your location along with sensor data, like whether you are running or walking. It also seems that opting out of these practices is not possible, unless you don’t mind not using the service.