Personally, the vast majority of the time I'm not in school/studying, asleep or doing daily necessities or the phone is out of batteries, which for a 14-yo without too much of a social life is usually upwards of 10 hours a day. This has been true for me for as long as I can rememeber really, I have pictures of 5-year old me playing flash games.
My time is usually divided as:
55% or so goes to this site, mainly because I like the discussion, it's more serious than reddit and we take our content more seriously. I would spend more if this site had more discussion, unfortunately. I have nothing to do in this site other than find something to comment in or post more often than I'd like.
25% or so goes to reddit, mainly for memes, places like imaginary maps, political discussion (although I gotta say, they're all fkin moderates) , true ask reddit and the ocasional stroll through the front page.
The remaining 20% is, roughly in order either YouTube or NSFW (depends on the day) and news.