OAKLAND, CALIF. >> Today’s widespread crashes of popular apps running on the iPhone’s iOS operating system — including Tinder, Spotify and Pinterest — serve as a reminder that Facebook is still tracking you through your phone using sophisticated software, even if you’re not browsing the social network.

Early today, users of the apps reported crashes when they tried to open them up. Facebook attributed the problem, which was quickly fixed, to a bug in its software development kit, or SDK, a tool developers use to integrate their apps with Facebook.

The integration allows people to use their Facebook credentials to log in to apps for dating, music or anything else. Google, Apple and other companies also offer SDKs to developers.

It also allows the app developers to send data from their app to Facebook, which tracks and measures what people do on the apps. The data is useful both for the app developers and Facebook, which uses sophisticated systems to measure how people respond to ads, how they use its service and how much time they spend on it.

In March, the video calling service Zoom was sued in California for sharing user data with Facebook using its SDK, a practice it now says it has stopped.

Facebook’s SDK caused similar crashes in May. The company said in a statement Friday that a “code change triggered crashes for some iOS apps using the Facebook SDK.”

The crashes Friday happened even if users were not logged in to the apps using Facebook.