Again Access... hey Access was a great database.
So if you are using access and you are thinking in how to use it from PHP or from a C/C++ app then you should check
mdbtools.
Does it work on iOS, well there is a discussion about at (http://old.nabble.com/Port-libmdb-(mdb-tools)-for-iOS-td34282658.html) but I think there might be some licensing issues.
If that is the case I would recommend writting your own version of mdbtools, Take a look at https://github.com/brianb/mdbtools/blob/master/HACKING for detail info about the file format.