I’m building an app that contributes to a crowdsourced earthquake early warning network: the device reports anomalous accelerometer readings, a server correlates them across nearby devices, and users farther from the epicenter get a warning seconds ahead. Detection has to continue while the app isn’t in the foreground. I’ve ruled out the obvious paths — CMMotionManager stops on suspension, CMPedometer and CMMotionActivityManager only return historical data, BGTaskScheduler is too infrequent, and CMSensorRecorder is watchOS-only. I’ve also read thread 765258, where DTS confirmed there’s no background capability for accelerometer data and that repurposing another one risks rejection under 2.5.4, so I’m not looking for a workaround. Is there any supported way to do this on iOS, for instance restricted to when the device is stationary and charging? Or is this outside what the platform currently allows? Thanks.
Is background accelerometer monitoring possible for seismic detection?
Update: I’ve filed this as an enhancement request — FB24275258 — asking for a purpose-scoped entitlement for background accelerometer access limited to seismic detection, with on-device thresholds and only trigger events leaving the device. Still interested in whether there’s a supported approach today that I’ve missed.
Thanks for your enhancement request.
You can see the status of your feedback in Feedback Assistant. There, you can track if the report is still being investigated, has a potential identifiable fix, or has been resolved in another way. The status appears beside the label "Resolution." We're unable to share any updates on specific reports on the forums.
For more details on when you'll see updates to your report, please see What to expect after submission.
Albert WWDR