The Roku 4 is an easy way to add hundreds more streaming channels and 4K content to low cost 4K TV's like LG's4K Ultra HD Smart TV with webOS 2.0 (2015).
Setting up the Roku 4 on the LG TV is the same as on the Vizio 4K Smart TV (click here for more details) except for that you can use any of LG's HDMI ports since all of them support 4K capable HDMI 2.0.
Roku really shows how good text and menus can look on a 4K screen. Not only can you get popular shows like NetFlix, Hulu, YouTube, but you can search and find a streaming channel for almost any interest or topic.
The best thing though about the Roku 4 is that is makes it very easy to find 4K content and actually play good quality 4K content whether on YouTube, NetFlix, Amazon, etc. Other 4K media players like the Sony Ultra HD 4K Media Players have much more limited content. Even Amazon's new Fire TV (2015) draws users mostly to Amazon Prime 4K content which is harder to find and sometimes doesn't even play correctly as 4K with the LG TV.