How large should I make a Geofence?
Having the correct sized Geofence for your location is very important. Geofences work by checking you in and out when you cross the boundary, so a larger Geofence will always perform better because when you are in the center of the Geofence you will be farther away from the boundary. Geofences use low power methods for determining your location that are less accurate than using the phone's GPS, so a Geofence that is too small may result in being checked in and out because of being too close to the Geofence's boundary.
A good rule of thumb is a Geofence radius of 150m or twice the size of your location, whichever is larger. A larger Geofence may be needed depending on the number of users, the size of your building, and surrounding WiFi in your neighborhood. If you experience any erratic behavior, you may need a larger Geofence. On the web interface, we present a warning message when your Geofence radius is less than 150m, and we don't allow for a Geofence radius of less than 100m.