Retention, we know, is critical to an app or product’s long term financial health. Mathematically, the arguments are incontrovertible—including the fact that upstream retention metrics have a cascading effect.

You’ve probably noticed by now: many apps (and websites) prompt you to sign in via Facebook. While it may often seem like a simple ask to make of a user, signing in via Facebook can have significant ramifications for an app’s retention metrics.
I saw this firsthand while working on a casual game: when we noticed the differential in retention rates between folks who sign in via Facebook and those who don’t, it was enormous. For this particular game in question, users signing in via Facebook had a 20-30% higher upstream and downstream retention rate than those who weren’t.