META Meta Platforms Inc

By Parmy Olson and Sarah E. Needleman 

A number of popular apps such as Spotify and Tinder experienced outages for several hours on Friday because of what Facebook Inc. said was a bug in its software for iPhone users.

The issue relates to Facebook's software development kit, or SDK, which many developers embed in their apps to allow people to log into apps through their Facebook accounts.

"Earlier today, a code change triggered crashes for some iOS apps using the Facebook SDK," Facebook said on its developer website. "We identified the issue quickly and resolved. We apologize for any inconvenience."

Complaints from app users about the problem appeared to begin surfacing on Twitter around 3 a.m. Eastern time, suggesting the outage lasted for several hours. A Facebook spokesman said the company is working to determine exactly when the outages began.

The bug didn't affect users of Android phones or web users of those applications.

On social media, users of other apps including Pinterest also complained of their services crashing as soon as they opened them on their iPhones via Facebook.

This isn't the first time third-party apps have experienced technical issues because of Facebook. In May, a number of high-profile apps including Spotify, TikTok and Pinterest crashed upon opening. The Facebook spokesman said Friday's problem was related to an update with its SDK for apps on Apple Inc.'s mobile-operating system, but the company doesn't yet know if the exact cause.

"We're aware of some issues right now and are checking them out! We'll keep you posted," Spotify's support team tweeted Friday morning after the music app suddenly stopped working. A few hours later, the team tweeted again saying: "Everything's now back in tune! If you still need help, send us a tweet."

App makers rely on developer kits to integrate their apps with others, enabling people, for example, to log in with their Facebook, Google mail or other credentials. Facebook's kit is among the most widely used by app developers for this purpose.

Facebook's SDK helps apps with user on-boarding and retention, said Adam Blacker, vice president of insights at Apptopia, an app-analytics firm. People using an app for the first time don't need to come up with a new username or password if they sign up with their Facebook credentials, he said, and logging back into an app is just as quick.

App makers see risks, such as outages, in using Facebook's SDK as worth taking, Mr. Blacker said. Outages are infrequent and when they happen typically many app makers are affected, he said. "You're sinking and rising along with your competitors," he said. "You don't look any worse than" they do.

Software-development kits for apps have presented other problems for users. A 2019 investigation by The Wall Street Journal found that people's personal information was sometimes shared with Facebook even if the apps on their phones didn't use the social-media giant's software kit.

Those apps sent data without any prominent or specific disclosure, a finding that alarmed some privacy experts who reviewed the Journal's testing.

At the time, Facebook said some of the data sharing uncovered by the report appeared to violate its business terms. The company also said it told apps flagged by the Journal to stop sending information its users might regard as sensitive and that it would take additional action if the apps didn't comply.

The Facebook spokesman didn't have additional comment about the issue Friday.

Write to Parmy Olson at parmy.olson@wsj.com and Sarah E. Needleman at sarah.needleman@wsj.com

(END) Dow Jones Newswires

July 10, 2020 13:55 ET (17:55 GMT)

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