The film service delivers on-demand films without the need for a subscription and has content deals agreed with Disney and Warner Bros.
KnowHow Movies will make for a comprehensive set of streaming movie services on LG's 2012 smart TVs including Acetrax, Blinkbox, Lovefilm and Netflix.
Films on the app are available at the touch of a button with no annual subscription and you can buy or simply rent individual films in SD and HD quality.
With Disney and Warner Bros on board, films already on the app include Sherlock Holmes: A Game of Shadows, John Carter and The Woman In Black, while "cult TV shows" are also promised.
The full list of LG TVs to get the KnowHow Movies on-demand movies app is as follows:
LG also recently announced the first 3D-enabled game apps for its 3D Smart TVs, previously only available on smartphones, and joining its 3D World app.
Games including Air Penguin, which was the top downloaded game app in the U.S. and 18 other countries last year, Frisbee Forever, Burn The City, Downhill Bowling 2 and Diversion from Unity Technology, have been optimised for LG TVs.