The Facebook iOS app on your iPhone is probably still set to upload lower-quality video by default. There is a setting you need to change to ensure that your Pearl videos are shared to Facebook in HD. Then there are two different ways to turn on HD video playback depending on whether you are using the Facebook mobile app or the website.
1. Change the video upload settings for the Facebook app to turn on “Upload HD”. Go to your iPhone’s Settings -> Scroll down and tap Facebook -> Tap Settings again in the Facebook settings -> Scroll down and toggle on “Upload HD”
2. When playing videos in the Facebook mobile app, make sure to tap the little “HD” symbol on the far right end of the video player bar (i.e., The “HD” will change to white text instead of gray). This will make the video play in full HD with crisp images and richer audio.
3. When playing videos on the Facebook site from a computer web browser, make sure to tap the little gear icon on the far right end of the video player bar. Then, turn on “HD” in the small menu. This will make the video play in full HD with crisp images and richer audio.