My wife loves it. Says it keeps her coffee super hot like she likes it. Only complaint is it is rather small for a travel mug. If it were a 16 or 20oz, it would get 5 stars.

Not very impressed. Battery life is underwhelming. 3 hours is being generous. Although, that amount of battery life could have been tolerable if the mug was actually insulated. It is not. It starts to get cold as soon as the battery dies. Unfortunately, a decent insulated travel mug will outlast this tumbler. This may a relatively harsh review but given the orginal price of $199.99 the return on the investment would not be worth it at a third of the price. However, it does what it advertises and the tumbler and charger base seems very well made. The App works well but not really necessary. One last thing that could improved it's usability would not have been to limit you to their proprietary charger base that only allows you place it on top of it, with no locking mechanism. If they had thought of adding locking, non-tipping, cup-holder friendly features, you could of easily used it as an in-car charger too.

I have many EMBER products and there the best and I love them all.