PDF Annotations are supported on devices using the Files Advanced app version 7.5 and newer.
Note: PDF and TXT files will auto-save 2 minutes after the first changes to the file or immediately if you leave the Files Advanced app.While in Drawing mode, the file will auto-save after you make another action or you exit the mode.
Note: You will be asked to set an "Author Name" the first time when you tap on the Edit button or try to add annotations. This name will be used to identify which user last updated the file.