Apple has already sought to patent some elaborate water damage detection methods, but it's also a fan of the classics. That must be why it's still attempting to patent a water detection method that it's been seeking since December 2006, just a month before the iPhone went public. The concept is a simple one that you'll find in many iPhones (and other iOS devices) so far: water-reactive, color-changing tape positioned in a device such that the Genius Bar staffer can see that your device took a dive in the swimming pool without having to tear the phone open. Mercifully, the patent factors in a membrane to prevent an overly humid day from triggering a false positive. There's still no immediate clue as to whether or not Apple will receive the patent, which strikes us as odd for a technology that's been used in the field for so long -- not that the company has needed the USPTO's blessing to void the warranty (or offer a rare free replacement) for more than a few waterlogged iPhones over the past five years.
Update: After a little fine-tooth comb inspection, we've found that this is the long-awaited granting itself, not just a continuation. Apple will be happy, although others trying to use a similar water detection system will be turning red... for reasons besides getting wet.