You are:
A television
They put pictures on me
then take pictures of me
to share with the world
You put "moving pictures" on a television. Some people might take a picture of their new TV to share online with their friends.
But the pictures disappear
as my end draws near
and anxious heartbeats stilled
After a person finishes watching TV, they power it off, causing the pictures to disappear. "Anxious heartbeats" could refer to the thrill that comes from an episode of a show that ends on a cliffhanger -- as you turn off the TV and move on with your day, you think about the show less, thus "stilling" your heartbeats.
I am sought after very wide
especially after every night
when things are put in motion
Modern TV's are built with a wide aspect ratio. A person who is really into a TV show will want to sit down and watch more every night as the plot of their show picks up.
And after a little while
I will be able to defile
your ability to sleep with devotion
As a person gets really caught up in their show, they may become "glued to the TV", giving up sleep in exchange for more time binge-watching their programs.