A:Answer hank you for a great question on our new SmartCast™ E55-D0! Because VIZIO SmartCast™ puts control of the display into your mobile device, we’re now able to make updates much faster and more frequently, right to your VIZIO SmartCast™ app. This TV does not have a tuner built-in, but does have multiple HDMI ports. In order to achieve the best picture quality and to take advantage of the 4K Ultra HD technology, it is recommended to use the HDMI connections. Most high definition cable or satellite boxes have an HDMI output. If using the coaxial cable is a must, there are external turners that can be purchased. We realize this is brand new technology and it takes some time to get used to it. That’s why we’re committed to continuous improvement which is going to make VIZIO SmartCast™ the best streaming experience and easiest way to control your display from anywhere in your home. If you have any questions or concerns, we encourage you to reach out to our Support team at 844.254.8088. Thanks again and have a great day! -Jesse