The base station communicates with the Smart Sock via Bluetooth connection. Only when you wish to view direct data via the Owlet app or to the installation process do you need WiFi. The base station serves as the main alert system, which means that even if your WiFi connection is interrupted or your mobile phone stops working (or if you miss a mobile phone), the base station will still be able to deliver notifications. Although WiFi is not necessary, it enhances the user experience. Use of HotSpot WiFi is not preferred.