When I flew my SPARK, the Go4 app had an option to record audio to the device when recording video for future use.
I learned a while back that Hollywood uses a clapper board for each scene as a visual and audible cue to assist when syncing the two.
I had an extra phone and used a clapper app that I would use in front of the SPARK camera while recording before lift off.
A Clapboard always at your fingertips! Completely redone, fast and accurate!
play.google.com
Clapping of the hands worked as well.
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