Designed for home or office, the new Ember Mug² does more than simply keep your coffee hot. It allows you to set an exact drinking temperature, so your coffee is never too hot or too cold. The smart LED indicates when the beverage has reached its perfect temperature. Select your temperature range from 120°F - 145°F (50°C - 62.5°C) on the mug or with the Ember app. The built-in Auto-Sleep function intelligently senses when to turn on and off. Ember maintains your chosen temperature for up to 1.5 hours with the Ember Mug² when off the charging coaster. If you are using the coaster, it can maintain your perfect temperature all day! The Ember Mug² is safe to hand wash and is submersible up to 1 meter in water. It is compatible with Apple devices running iOS 12.0 and above, and Android devices running version 8 and above. Once your Ember Mug has an empty battery, place the mug on the charging coaster for approximately 2 hours for a full charge.