Problem when connected with custom smartphone app for extended duration

[WoutZenso]

Hi,

We have designed a wearable device for one of our clients with the nRF52832. The MCU connects to a smartphone and streams sensor data during the whole duration of the test (might take up to 10 hours). Our client developed their own smartphone app to take care of the sensor data and to push the data to their server. However, with more and more people using their device, they notice that there are sometimes problems where the OS seems to kill their app or even turns off bluetooth on the smartphone. This is both on Android and iOS (older and newer versions). I am well aware that this issue is most likely purely app/OS related, and not related to the nRF MCU,but I hope someone here might have been in the same situation before. Are there best practices when trying to keep an active (Bluetooth) connection for extended duration with a smartphone? Is there any way to prevent the OS's smart battery management system from turning off Bluetooth or killing an app that needs to be active all the time?

All your input is welcome!

[Kenneth]

Hi,

I believe iBeacon was designed to start an app on the phone, so you may consider looking into starting or having the peripheral to advertise using iBeacon intermittently to start the app again on the phone.

Best regards,
Kenneth

[Fred]

Also - just to be sure - you might want to check whether your client enabled background processing for the app (for iOS see this).

[WoutZenso]

Hi Fred,

Thank you for your feedback. I checked with them and they assured me this is already enabled.

[WoutZenso]

Hi Kenneth,

Thank you for your feedback. I will tell our client to look into this. This is of course not the solution to why the app gets killed, but it looks like a good fail-safe mechanism to get the app back up running after it has been killed.