Question: how to connect iphone to lg tv to watch movies?
Answer: Launch the Mirror for LG TV app. It will start looking for your LG TV(s) on your local network. When a TV is found, select it. ... 
Click on 'Start Mirroring' to start mirroring on the TV that is currently selected.
Select 'Mirror LG TV' and press 'Start Broadcast' to start mirroring on your selected LG TV.