No Brainer

A smart phone camera holder for all seats in roller coasters so you can take a selfie video you taking the ride.

First you start the camera video recording. Then you put the phone in a padded holder so any size phone is held in place without moving. When they lower the bar, the holder flips closed to secure it during the ride.

Another version is there's a camera on every seat facing the riders and at the end of the ride you buy the video that's messaged to your phone number.