Devices running iOS 11 and later can store photos and videos using a high-efficiency compression scheme called HEIF/HEVC. Video saved in this format cannot be displayed in Logger Pro or in Vernier Video Analysis. Inserting such a video will generate a blank box, or a Movie Load Error message may be shown:
Apple is aware that many applications cannot read this format, and so they provide a “More Compatible” format option.
The solution is to set Camera Capture Mode to Most Compatible in iOS settings. The path is Settings > Camera > Formats > Most Compatible. Make this change before capturing videos.