Myk downloads the video files to an app working directory.  They are not available in the iPhone library until you finish mixing.  The Myk downloaded working files can be automatically deleted after mixing (option in settings), or you can manually delete them when you want to free memory space.  To delete old working files, use the media manager.  Media Manager only manages Myk working files, and does not touch the iPhone libraries or albums.  If you are downloading HEVC high definition files, we will place the file in the Myk storage database for iPhone 7 and below, since those phones do not support HEVC file storage or playing.