It's founded by Evan Williams[1] of Blogger, Twitter etc.
Obvious have invested/incubated Medium, Branch, Jelly, Lift, Beyond Meat, Good Fit and Neighborland. (There may be more but I'm pretty sure that's all of them)
Medium, Branch and Jelly are what the Obvious founders are now focusing on (although they sit on some of those other startups boards):
Ev - Medium, Branch - Jason and Jelly - Biz