With the FRIENDS & FAMILY subscription, each helper needs our SmartWatcher® app and thus a smartphone and internet connection. Our app can be downloaded for free. With the FRIENDS & Family Plus subscription, our app is not necessary for the helper, but if there is at least one mobile phone number added as helper, also at least one helper needs to download and install our SmartWatcher® app. It's not necessary for the other helpers unless they want to use the SmartWatcher® app to see the wearer's geolocation in case of an active alert. 

See also: Do I have to pay for the SmartWatcher® app?