Okay, this is not an android app, but you can use it to read your sd card formatted in your Android phone and recover files off a bad card.
I'm using testdisk on a vista computer reading from an sdxc card that was formatted in my Rezound.
I had pulled my card and hooked it up to my computer to delete a PHzip file and then my phone wouldn't read it when I put it back in. Then when I put it in my computer that wouldn't read it either. Fortunately testdisk is working so I can retrieve all my back ups.
After you select the drive and it comes up with the partition table list, select [None].
Then select [Analyse]
Can't recall exactly what happened next, I think it mentioned errors with the partition etc... but it listed the correct size of the card if it were empty so I proceeded and then bam, it listed all my files. Copying them all off now.