If you're a photographer, then you know that a cable release is a tool to take a picture without touching your camera. Now, the iPhone can do this, too.
iOS 5 introduced many new features for photographers. Among these is the ability to use the Volume up button to take photos. As a result, the Volume up button on your headphones also works to take photos! It seems perfectly obvious that it should after the fact, but it's not something most of us are likely to try.
This means, every iPhone includes a free cable realease. This is huge for an iPhone photographer because the current shutter buttons aren't very good for keeping your phone steady. Interestingly, I've found that it's often much easier to get burst shots when using my headphones compared to just the volume up key.
Perhaps the best part is that this can be paired with Bluetooth devices! I'm not sure if every headset with volume controls will work (as the buttons need to map correctly to the iPhone), but if a Bluetooth headset can increase the iPhone's volume it should work.
What I have been able to confirm so far is that a Bluetooth keyboard is perfectly capable of acting as a remote. In addition, Joseph Linaschke over at ApertureExpert.com has said that his Bluetooth headset works as well, but I'm not sure which model.
Using a wireless remote opens up even more possibilites, especially when considering that the remote will start and stop video capture, or take self portraits which don't have your arm in the photo.
Hope someone else will make use of this for their iPhone photos.
[crarko adds: This is a great find. Please share the results of your device testing in the comments.]
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