Fast / Smooth Loading Speed for Videos on ios App

I am currently running a social app on ios using firebase as the database and firebase storage for the video storage. The app is similar to Tik Tok and has a lot of videos that need to be played very quickly on users devices. Sometimes videos are a little slow to load on the current setup. I am looking to improve loading speeds and make the videos very snappy. I was thinking to either implement a much better video compression that will keep the HD quality while dramatically reducing video size. OR to implement HLS for dynamically streaming rather than downloading and playing videos. Looking for someone to help me get this fixed.