There’s a reason why social media profiles have become a popular means of logging in across the Internet. As recently as 2015, we saw more than 58 million logins using social media credentials across 700+ other apps and services. I can’t take credit for even a single instance, but I certainly understand why the numbers are so high.
It’s all about convenience. It’s why so many of us use our credentials on Facebook (which has the lion’s share), alongside Twitter, Google and also Yahoo to log in to other applications — and why so many retailers offer that service to get customers registered on their sites.