Diagnostics on M7 motion coprocessor I own an iPhone 5S and use the apps Argus and Nike+ Move that utilize the M7 motion coprocessor. 

A few weeks ago both apps were unable to properly import motion data (they would hang when loading up trying to update motion information).

Is there any way to diagnose if the M7 motion coprocessor on my iPhone 5S is faulty?
Yes - you would use the health app and place steps and distance walked/run into your dashboard and then take the phone out for a walk or jog. 

If no data is logged, you can conclude that the processor is likely faulty. You could confirm it by backing up the device and restoring a clean OS and repeating the step test.