With larger sized SD-Card support and of course USB OTG support for USB sticks, hard drives etc, the quest for an optimal file system comes back to haunt us. There has always been a problem with external storage for cross platform users. Finding a file system that meets all the following criteria is very difficult as a good file system must:
- Be supported natively by all Operating Systems you use
IE. Windows, Mac, Linux and now Android
- Support large partition sizes
- Support large file sizes ( larger than 4GB files aren't so uncommon anymore which puts FAT out of the running)
Recently I came across the suggestion to use UDF as it meets all the above criteria. (see http://tanguy.ortolo.eu/blog/article93/usb-udf for an example)
I tested this idea with a USB stick and sure enough it was plug-n-play on Windows and Linux (and I assume Mac) but I was disappointed when I plugged it into my phone and tablet using USB OTG and USB.
I don't think there's any technical reason Android can't support UDF, rather no one has really thought to build the module and tools into their ROM or Kernel package.
I'd like to suggest that UDF be added as a standard module for ROM builders, along with NTFS, exFAT, ext 2/3 etc.as it would really give Android device customizers another really useful capability not available elsewhere. I'm especially thinking of people that carry around a lot of files on one USB stick that they use on multiple platforms. Like sysadmins, Movie buffs, business travelers, etc.