Yes. An active internet connection via WiFi is required in order to use the Hestan Cue app.
Most Cue-enabled cooktops and cookware require a firmware (software) update via the internet before they can be used for the first time. An active internet connection is also necessary when using the Hestan Cue app on your smart device as guided recipes, videos, and other multimedia all get streamed on demand
It is possible to use Hestan Cue without internet access after applying the initial firmware update, but you'll only be able to use it in manual (offline) mode (without smart functions).