The “C” button’s function is vestigial. Back when calculators were commercialized, starting in the mid-1960s, their electronics were designed to operate as efficiently as possible.

Again, this is an awesome new feature. Okay, the iPhone Calculator app has changed for the better, but I still miss the “C” button. This simple change shows Apple’s overall power.

Amnesty's 'Panic Button' app will continue to be developed throughout the end of this year, and you can check out the status of the project and its uses around the world on their blog.