Dummy cases, hand-delivered prototypes and two designs that never saw the light of day.
The secrecy surrounding the Galaxy S III was crucial in building anticipation ahead of the device's launch, and today Samsung has revealed some details of the phone's top-secret development process. Only a privileged few within Samsung were able to see the device, with design and engineering work taking place within a secured area at Samsung's Seoul HQ. Discussion with outsiders was forbidden, and the phones were apparently locked inside secure boxes for transportation, even within buildings.
Most interesting is the revelation that Samsung fully designed and built three versions of the Galaxy S III to further reduce the chance of the actual design leaking out. That'd certainly explain the appearance (and leaking) of a buttonless S III a few weeks ahead of launch. In today's blgo post, Samsung R&D engineer Woo-Sun Yoon confirmed the use of dummy cases like the one above in field testing, to protect the phone's true exterior from prying eyes.
“We had to make three types of the GALAXY SIII to prevent the design from leaking. And on top of that, whenever any of these had to go out for testing, we put them inside ‘dummy boxes’, which are cases that hide the design of the device, to disguise it. Even if people, inside or out of the campus, saw the device, I doubt they would have known what it was.”
And the security didn't stop once the devices were completed. Samsung says units delivered to mobile operators were transported in person and hand-delivered by its employees, and testing was done under strict supervision. All this resulted in the final design remaining a mystery until just a week before launch, when a Samsung service manual outed what we now know to be the Galaxy S III.
For all Samsung's pre-launch secrecy, it's now being incredibly open when talking about that secrecy. You'll find a full run-down of exactly how the S III was kept under wraps over at the source link.