Question

I understand that the accelerometer stops reporting data if the screen is locked. So you either have to disable the screen timeout and implement a custom lockscreen and that too isn’t a full proof solution because the user could switch to another app and invoke the lockscreen, which is why pedometers are so scarce on the marketplace. However is there any way for an app that is in the background to still be able to report accelerometer data if the user is multi-tasking?

I’m trying to design a pedometer and from whatever I’ve read and researched, it looks like multi-tasking won’t be an option when it comes to accessing sensor data. So if I have a pedometer app in the foreground that is recording steps, if I get a phone call or decide to read email as I’m walking or anything else that results in multi-tasking the sensor will stop reporting data since the app that uses it goes in to the background? Can someone verify this for me or let me know if there is some way to overcome this?

Answer 1

no

There is a set of APIs that cannot be used by any Scheduled Task. Using these APIs either will cause an exception to be thrown at run time or will cause the application to fail certification during submission to Windows Phone Marketplace. For the list of restricted APIs, see Unsupported APIs for Background Agents for Windows Phone.

Quoted from Background Agents Overview for Windows Phone

Microsoft.Devices.Sensors: All APIs in this namespace are unsupported.

Quoted from Unsupported APIs for Background Agents for Windows Phone