Recently, I've noticed that background Bluetooth scanning stops when I move an app to the background on an iPhone 17 device with Bluetooth 6. I'm curious about a solution. Background Bluetooth scanning doesn't stop on devices older than iOS 26, or on devices that were updated from an iPhone 17 or earlier to iOS 26.
iPhone17 bluetooth background scanning issue
This is likely due to the state of the specific device you are observing the issue rather than an iPhone 17 or iOS 26 issue.
When apps are in the background, the scanning slows down in stages, and the advertising interval of the peripheral is critical to being able to discover and connect.
Please do check what the advertising interval is. We recommend 20 ms, 152.5 ms, 211.25 ms, 318.75 ms, 417.5 ms, 546.25 ms, 760 ms, 852.5 ms, 1022.5 ms, 1285 ms intervals. Even with these specific intervals, using the slower ones, discovery can take up to several minutes.
So, I would believe the issue is not scanning is being stopped, but slowing down so you might be thinking it has stopped.
You can test this by changing the advertising interval of the peripheral to 20 ms, and then it should be discovered in seconds even if your app is in the background.
Argun Tekant / WWDR Engineering / Core Technologies