Flip bit position 5 to accomplish this. This maps to hex value 0x20, where the least significant bit is assumed to be at position 0.
Example: ascii "A" = 0x41, "a" = 0x61. 0x41 xor 0x61 = 0x20.
You would implement a flip function by XOR'ing the character value with 0x20.
Google intended the limited initial rollout to be a test of google glass, that the adopters were Innovators.
The initial rollout of Google Glass was limited, purposefully so as to set the price very high. This mean that only a selected few, and those with plenty of disposable income, would be the first to use these devices. Google required people to register for the chance to receive a set. Even if many would want to spend the money on these devices, Google allowed only a selected few to receive them.