How does Apple iPhone 7 plus slow down the speed of normal video shooting?

I can only press one software, which has slow motion.

1 and iPhone7Plus adopt a 5.5-inch LCD screen, which supports the resolution of 1920× 1080 at the highest, and the PPI reaches 400. If you shoot video at a high resolution of 1080P and set the frame rate to 60 frames, you will shoot twice as many video files as 30 frames.

2. In this case, if you record a video of 5 to 6 minutes, the file size will be more than 700 m, or even higher. The video file size taken by the mobile phone is related to the resolution frame rate adopted. The higher the set resolution, the higher the frame rate and the higher the video bit rate, which means that the greater the amount of video information per second, the greater the amount of video files generated. Usually, due to the limitation of the storage capacity of mobile phones, it is not recommended to shoot long-term videos with high resolution and high frame rate.