What is the English word for this device on which a smartphone can be put so that people can watch videos on the phone?

Answer 1

Hmmm! I'm not sure. There may be a device where you live that's not available in the US.

iHome and other charging stations enable you to play music, podcasts, etc., when you phone is plugged in.
https://www.ihomeaudio.com/

Roku, AppleTV, and Amazon Fire TV Stick are devices that will pick up the signals from your wifi system and play them on your TV. AppleTV will also pick up signals from your compatible laptop and/or iPad to play on the TV.
http://www.roku.com/
http://www.apple.com/appletv/
http://www.amazon.com/dp/B00CX5P8FC?_encoding=UTF8&showFS=1