Hi! If you tap on the auto fps, the next screen will reveal a bit more information about this setting:
I guess people could use it to save space on their videos. Also, it says here that 30fps helps to take videos in low-light environments.
What's the default setting, btw?
I tried it on a couple videos. After putting the video on my pc I noticed there are some points in the videos where the frame rate will get choppy. I’m guessing this is the frame rate switching. Not a fan of that.