WWDC 2012 Session 709, What’s New in the File System, presented by Deric Horn included the following observation: Journaled HFS+ everywhere.

In the iOS Developer Library, NSDictionary Class Reference contains references to HFS.

Do iPhones use HFS Plus?

Journaled or not journaled?

I'd like an authoritative reference. Thanks.

Types of HFS Plus

iOS and iPhone aside for a moment … Apple's hdiutil(1) Mac OS X Manual Page lists four HFS filesystem types for creation purposes:

  • HFS+
  • HFS+J (JHFS+)
  • HFSX
  • JHFS+X


Beyond the accepted answer … as Apple sometimes distinguishes between JHFS+X (journaled, case sensitive) and HFSX, so:

… I do have fileXray, but I don't foresee myself making an ssh connection to my first generation iPhone ;-)

  • 1
    Background: twitter.com/jollyjinx/status/395193114941734912 observes breakage of an original photo on an iPhone. – Graham Perrin Nov 1 '13 at 8:33
  • Weird, I sought answers a few times before posting this question. I don't know how the duplicate was missed. Maybe because I sought iPhone instead of iOS. I'll add a tag to the earlier question. – Graham Perrin Nov 1 '13 at 19:36

According to iOS Forensic Analysis, the main filesystem is HFSX.


All Apple mobile devices use HFSX as the file system. HFSX is a variation of HFS+ with one major difference. HFSX is case sensitive.

HFSX is reported by Apple as Mac OS Extended (Journaled, Case-Sensitive).

There are two main partitions of HFSX: the OS and the user data. Prior to these partitions is the usual MBR partition (around 100 MB).

SSHing into my jailbroken iOS 6 device seems to support this, since I can create case-sensitive directories. Creating the following directories was no problem:

$ mkdir test
$ mkdir Test
$ mkdir TEST
| improve this answer | |
  • In the book neither JHFS+X nor JHFSX is mentioned, which made me wonder whether it's case-sensitive without a journal. But then, where Sean Morrissey uses fileXray: kHFSVolumeJournaled (volume has a journal) … I wonder whether that's true for both HFSX slices of the disk. I'll add something to the question. – Graham Perrin Nov 1 '13 at 8:02
  • If all goes well, after iOS 10.3 they will be using APFS: arstechnica.com/apple/2017/01/… – Andrea Feb 12 '17 at 15:32

Not the answer you're looking for? Browse other questions tagged .