The home area is a setting in the app which lets you define your home zone radius. The Viva app uses the home area to detect when you are coming home. When you enter the home area the Viva app will increase the frequency of location querying in order to tell your home when you arrive with high accuracy. The home area can either be set to 150m (small) or 300m (normal) radius. 300m is reccommended for normal use.