App: Switching between Fahrenheit and Celsius You can switch between Fahrenheit and Celsius using the settings icon on the Ember mobile app. Related articles What is the Charging Coaster Voltage? Travel mug: Can I use it without pairing to a phone? Travel mug: Can my Ember be used to warm up drinks from room temperature? Travel mug: Will it keep my drink cold too? Travel mug: Is my Ember safe to leave on charger?