Hamster Pad - A social network built on top of Slack
Planetary - Decentralized social media by and for the people.
Kaboom by Hotspot Shield - Share messages & photos that disappear on any social network
DeSo - DeSo is a new layer-1 blockchain built from the ground up to scale decentralized social applications to one billion users.
Tsu - Social that pays
Manyverse - A social network off the grid