According to a report by TechnoBuffalo Apple and Verizon were very careful to make sure that the iPhone 4 launch stayed under wraps until the announcement. A source close to the process claims the device was codenamed Acme and employees were privy to information only on a need-to-know basis. Some were testing Verizon connectivity at Apple stores up to six months in advance of the February release.
Some Verizon employees received iPhone 4 units two weeks prior to the official launch. This privilege required the signing of a four-page non-disclosure agreement (NDA) from Apple before they could get their hands on the device. The CDMA iPhone 4 itself had unique security features to ensure that a device wouldn't go missing as happened in 2010 with a prototype GSM iPhone 4.
Users were required to type in a passcode every 12 hours to verify the pre-release Verizon iPhone 4 models hadn't fallen into enemy hands. Verizon kept everything quiet up until the last minute, when they distributed invitations to a special announcement scheduled just two days after the Consumer Electronics Show (CES). Speaking of CES 2011, not a peep or even the slightest hint of a CDMA iPhone 4 was leaked to the press by Verizon, despite numerous reports in mainstream media that the launch was imminent.
As they say the rest is history, with the iPhone 4 hitting Verizon Wireless in a big way. The release was more of a steady, slow burn than a crowd-inducing camping and stand in line event. Nevertheless Apple and Verizon's strategy to keep the device secret worked, and the buzz surrounding its release never really faded until the actual announcement on January 11.