A major Facebook bug caused a large number of iOS applications to crash on Wednesday for more than three hours, according to reports on GitHub and social media.
The bug impacted some of the biggest iOS apps today, including the likes of TikTok, Spotify, Tinder, Venmo, GrubHub, Doordash, Soundcloud, and Pinterest, just to name a few.
According to technical analysis of crash logs posted online, the issue was tracked down to the Facebook software developer kit (SDK) for iOS, a library that developers include in their apps to support features like Facebook sharing, the Facebook social graph, or Facebook logins.
Developers said the Facebook SDK for iOS called to Facebook's servers every time a user would launch an app that included the library.
The issue was that the SDK was expecting a server reply in a certain format, which on Wednesday, the Facebook servers were not providing.
Without the proper response, the Facebook SDK crashed, also bringing down all the apps that used it.
While Facebook has not made any formal comments on the incident, the company appears to have rolled out a patch to its servers more than three hours after crashes started being reported.
Nevertheless, due to the sheer size and impact of the bug, several hashtags like #tiktokdown and #spotifydown trended on Twitter late Wednesday night. More on the bug in this GitHub bug report and this HackerNews thread.