VIZIO SmartCast E-Series 55” 4K Display

Is this actually a smart TV or does it just have the Chromecast built in as a cheap alternative and no apps like Netflix, Vudu, etc.?

doesn’t sound like it

From the vendor:
This is a Chromecast TV, however, you need to use an external device such as your phone or tablet in order to access the apps such as Netflix, Vudu, etc.

I have this TV in a 65". I love the app feature (Smartcast) over using the included minimal remote. The TV connects to your home wireless router. Your phone then becomes a full featured remote. You can switch between HDMI ports and cast YouTube videos. I actually watch movies from my phone using the VidAngel app and cast it to the TV in 1080p. The TV has built-in Chromecast.