How to track heart rate on both 965 and HRM dual?

I keep seeing oddities in the heart rate from my wrist watch so I purchase the garmin HRM dual chest strap and want to record BOTH the heart rate from the watch AND the chest strap so I can compare them and determine if there are things I can identify which are causing the wrist watch anomalies.  I found that this could be done with an app, but that app is not supported by the 965, is there any other way of doing this?