This is a new Twitter sign-up flow that existing members can also use. Not so much a product, it's more of a way to customize your Twitter profile and discover other accounts related to the World Cup.
I don't recall Twitter ever launching a feature like this so it's interesting to note what they're doing to drive engagement and new signups around a big a event.
The concept of re-onboarding in general is interesting. One of our companies (BirthdayAlarm) is over 13 years. This means there are double digit millions of members who have not updated their social graph in 10 years! I wonder what type of re-engagement and viral growth we would see if we funneled them through a re-onboarding..
MostPopular.xyz
Terrible horrible no good very bad ideas
Robomart