What to do: Soak the coffee-stained cup in a mixture of white vinegar and water for a few hours. After, scrub the stains with ...

Fill your mug with hot water and let it rest for 10 to 15 minutes in a safe place. The right temperature is around 120 degrees Fahrenheit, which is about as hot as tap water can get in most homes.

The Ember Mug 2 is the top smart mug in our best coffee mug guide because it aims to make your cold tea and coffee woes a thing of the past with temperature controls you can configure from your phone.