I'm seeking information about the original file schema for an m4a file recorded directly on an iPhone (iPhone 5 running iOS 9.2.0). I currently have two files from which I extracted metadata using ExifTool. The first file was provided to me by someone who claims it was recorded on an iPhone 5 with iOS 9.2.0. I would like to verify whether this file has been edited. File Permissions: -rwx------ Content Create Date: 2016:03:01 14:21:08+07:00 The second file was recorded by me on the same device model and iOS version. File Permissions: -rw-r--r-- Date/Time Original: 2024:10:03 11:44:16+07:00 As you can see, the file permissions differ, and the key for the recording date also differs: one uses "Content Create Date" while the other uses "Date/Time Original." I would like to determine if the first file was edited, but I haven't been able to find any official documentation on the m4a schema or metadata structure from audio recorder apps. I reached out to support, and they directed me to this forum. Any insights or help would be appreciated.