We've already seen pictures (and video) of the water-defiant Samsung Galaxy S 4 Active, so despite its unannounced status, it's difficult to refute its existence. Fortunately, we're starting to get even more evidence that its launch is rapidly approaching, as an AT&T-compliant version of the rugged device -- the SGH-I537 to be exact -- has made its way through the federal approval process. As you may already know, this is by no means any guarantee that it
