Google recently conducted a study into multi screen viewing habits (ok, another study). It results in a pretty interesting infographic.
Some standout stats:
90% of people use multiple screens sequentially (moving from one screen to another, eg from a phone to a laptop), 67% while shopping online .
77% of the times that viewers watch TV, it’s not on a TV (49% smartphone, 34% PC/laptop).
These numbers aren’t really trends (those were established some time ago), they are more revealing as the growth of the trends.