This is a pretty good thing to have if you happen to be working at your desk and want you coffee or drink hot. It does have a built in battery so you do not have to worry about it not continuing to work after you take the devices. The first thing I will say about this is that the mug does not have as much space as you think it does. It might have enough for a cup of coffee but a 1/3 of the mug is mostly just the heating component of the mug as well as the battery. Most of the bottom and outer edge is all electronics. The mug itself is big but the amount of fluid inside is not as much so be aware of that. The mug does have digital LED indicator on it. It is just a simple press of the button. The button is a bit sensitive though. It is just touch and not press based. Just touching it turns the screen on. It will tell you the temperature and heating. I did not see any issues with the cup actually getting super hot on the outside so you do not have to worry when you pick this up. The device is panel charged so you do need to place it on the panel when you want to charge it. It is recommended that you CHARGE IT first before use. The bottom does not get super hot or anything. The device is powered via type c and there is an actual power brick for the actual device. This is good because the actual pad is also fast charging for phones. It is wireless charging. You could just use type c to usb but you will not be able to charge the mug and only your phone. The actual power cable is pretty long but it is a power brick as the end so it would take up more space on the actual outlet. The inside does not chip or fray and is pretty easy to clean with a bottle brush. I only hand wash and air dry for this as I am not sure the electronic is able to be dish washed. The controls are pretty simple. It tells you battery life, temperature you want to heat it to and if the device is on. It does take some getting used to but you can easily just read the manual. The manual is simple but detailed enough to help you use it. The device battery works pretty well. It will shut off when it reaches the temperature which is nice. Overall this device is good for having at your desk. It is nice it can heat your drink as well as keep it warm. It does shut off on it's own so you do not have to worry about it overheating. The lid is not bad but it could be a bit better built. Regardless the material of this is heat resistant so you do not have to worry about burning yourself. It is pretty easy just to place it on the charger. The phone charger is a nice touch and it is fast charging. I like that it comes with a pretty powerful power brick. The only thing I will say is that I wish it could hold more liquid and also the power button was not as sensitive as just gripping it could actually turn the device on.