No, the Cinder Grill can be used without the app — just set the temperature manually by turning the dial and waiting until Cinder beeps to let you know your food is ready.
However, the Cinder app provides a better set-it-and-forget process: Select the food you're cooking from a list, choose your desired doneness (e.g. rare, medium, well done), and Cinder will not only estimate how long cooking will take (P.S. Cinder is faster than sous-vide), but it'll notify you when your food has reached temperature.
That's all there is to it. We've kept the app dead simple. It gets out of your way.
The Cinder App is currently available for iPad and iPhone, and the Android app will be developed once we hit our Indiegogo fundraising goal.
Choose your contact method on our Contact page, and we'll be happy to help.