.MDBACKUP File Extension
What is an MDBACKUP file?
iPhone or iPod touch backup file created by iTunes, a digital media player; contains backup data for the device, which may include notes, SMS messages, pictures, contacts, and other data; used by iTunes for restoring device states.
The data in MDBACKUP files are stored in a proprietary format which is only meant to be used by iTunes. However, some information may include plain text data, which can be read with a text viewer.