Its ok... but crashes

I bought 800 dollars of camera equipment for my iPhone 6s Plus for videotaping. I bought the app because it had some really good features. Worked great for about a few months then 2 updates ago it wont open. I push the app, it begins to open then crashes. This is repeated for 15-20 times till either it works or I get fed up and use the camera on the phone instead. Needs fixed.

Hillbilly puck about Filmic Pro－Video Camera, v5.3.1