screen time

or screen·time

[ skreen tahym ]
/ ˈskrin ˈtaɪm /

noun

the amount of time devoted to a particular actor, topic, plot line, etc., in a film or TV show: The female characters got less screen time than the male characters in all the film festival nominations.
the amount of time a person spends watching or interacting with content on the screen of a computer, phone, TV, gaming console, etc.: How much screen time does the doctor recommend for children under two?

Origin of screen time

First recorded in 1915–20, and in 1990–95 for def 2