Corbett Report starting a new series where he goes searching for social media alternatives to Twitter, Facebook, Youtube, etc that arent under corporate control.
https://youtu.be/50IZSxYi68k
Also here's some that I have explored. Of course, they will get better with more users and content, but for now I use Riot for private messaging.
Blockchain Twitter Alts:
https://leeroy.io/
https://peepeth.com/
Blockchain Youtube Alt:
https://about.d.tube/
Blockchain Blogging Alt:
https://steemit.com/
Blockchain messaging:
https://about.riot.im/ (built using the Matrix messaging Protocol :
https://en.wikipedia.org/wiki/Matrix...tion_protocol))
https://www.kik.com/developers-blog/ (Technically, I believe the messaging side is not utilising blockchain, but it does feature a currency available for kik users)