You need to use the app for initial setup, and to connect the infuser to the WiFi network. Although it isn't 100 percent necessary after that, you will find that your Teforia experience will be limited.
With the Teforia Leaf you are required to use our Sips to brew tea, because the RFID tag in them tells the Teforia Leaf the correct recipe to pull up.
With the Teforia Classic you will also be able to use our sips to brew tea, but if you want to use your own teas, you would be unable to do so. Why? The Teforia cannot pull up the right recipe for your tea without you answering a few questions about the tea in the app first.