I recently picked up a HDHomeRun device to transmit my OTA antenna to all my TVs and mobile devices. While I love Plex as a DVR solution, I prefer Channels for watching live TV. It's available on iOS and Apple TV.

Channels does precisely what it says it does. You launch the app, it finds your antenna, and shows your channels (with a full guide). It starts TV channels extremely fast (this was some of my frustration with Plex for live TV). You can pause and rewind live TV, you can view closed captioning, and it also supports 5.1 surround sound. The company behind Channels also built a DVR solution if you want to go all in.

If you are wanting to "cut the cord" in 2018, Channels for Apple TV and iOS (along with an antenna and a HDHomeRun. I pick up 29 channels (most of them in HD). You can see about your area on Antennaweb.

Channels is available on the iOS App Store for $14.99. It's on the Apple TV App Store for $24.99