Do I need to use the app with Cinder?
No! Cinder Grill works 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. Use the dial for temperatures above 200 degrees F and use the Cinder Grill app for temperatures below 200 degrees F.
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.