- Extension
- .m4r
- .opml
- Format
- Binary
- Text
- Category
- Audio
- Document
- Developer
- Apple Inc.
- Dave Winer
- Description
- M4R is an iTunes ringtone file that stores mono channel audio. They are identical to the M4A format files only that they are correctly used for ringtones.
- OPML (Outline Processor Markup Language) is an XML-based format used to exchange outline-structured information. It is most commonly used to share lists of web feed subscriptions (such as RSS or Atom feeds) between feed readers and aggregators.
- MIME Type
- audio/x-m4r
- text/x-opml
