The use of the discovery+ app on your mobile device via Wi-Fi will count against your internet data plan when used at home, but not your cellular data plan. Watching discovery+ on any device connected to your home network or Wi-Fi will consume bandwidth, as with other streaming services. If you are using a free Wi-Fi network outside the home, the service will not count to your home internet plan or cellular data plan. If you stream content using cellular data, it will count towards your mobile plan.