Live Activities in iOS 18 to Refresh Less Frequently, Impacting Real-Time Apps

With the release of iOS 18, Apple has made changes that will affect how often Live Activities can refresh on your device. According to feedback received from a developer, Live Activities will no longer be able to update as frequently as they could in iOS 17 and earlier versions. While this change may not impact most apps, it’s a notable update worth discussing.

The Issue

App developer Nico recently shared on X (formerly Twitter) that his application, which previously could refresh Live Activities every second, will now only be able to update every 5 to 15 seconds in iOS 18. This poses a challenge for his app, where real-time data such as bicycle speed was displayed using Live Activities. With this change, the displayed speed will lag by about 10 seconds, which could be problematic for certain real-time applications.

Apple has clarified that this limitation is intentional. The company explains that each Live Activity update writes data to disk, which can cause excessive wear on the device’s NAND storage. This issue is particularly important with iOS 18, as Live Activities now sync with your Apple Watch through watchOS 11.

Additionally, Apple mentioned that Live Activities were never designed to support “real-time experiences” and that the previous ability to update so frequently was unintended—a “hole in the API” that they are now closing.

Developer Concerns

Interestingly, despite Apple’s new stance, they have previously used a similar use case as an example for Live Activities on their developer website. Apple had suggested that a workout app could display real-time fitness metrics. However, it appears that Apple no longer intends to support this kind of use case in iOS 18.

Impact on Users

This change shouldn’t impact Live Activities that include a countdown feature, such as those used by apps like Uber or Lyft, which display an estimated arrival time. These apps only push an update when the time is initially set, and then the Live Activity handles the countdown internally without frequent updates from the app.

Apple first introduced Live Activities in iOS 16 as a way to provide users with quick, important updates directly on the lock screen or Dynamic Island. With iOS 18, however, the functionality is being refined to reduce wear on device storage and avoid real-time data use cases.

Conclusion

While this update will likely go unnoticed by most users, developers who rely on Live Activities for real-time data display will need to adapt to these changes. It’s crucial for developers and users alike to understand these limitations as iOS 18 rolls out.