Yes, you need to have an internet connection to find a nearby inthesk as it uses Bluetooth to connect.

The inthesk application will also remember the last known location when your inthesk was connected to your phone. If your inthesk was last connected to another mobile device, you will need an Internet connection to get the location through the inthesk system. You also need an Internet connection (data or Wi-Fi) to register or log in to the | inthesk | app, to initially pair your inthesk. Once logged in, you do not need internet access to connect to your inthesk via the app.