Q: How to get a video from the built in video app to camera roll??

So i recorded a few clips on my PS4 transferred to my laptop then i needed to use a third party app to get the video on to my ipod  but it goes straight to the builtin video app instead of camera roll. Really starting to **** me off i already had to use a third party app because itunes is trash any idea on how to get the video to camera roll.