I use it only to communicate with my personal friends, arrange social activities etc. I have it set so people can't get anything useful about me unless they are my friend, and I am very careful about who I add. I have even refused all my family except for my sister. Not that I don't like them, I just don't want them to know about my personal life. They probably would not approve of some of it.
I don't use any apps, or subscribe to anybody, but a lot of the good stuff shows up in my feed because my friends subscribe to all that stuff. I do enjoy I Fucking Love Science.