Google and Apple are having trouble keeping their Google Voice story straight. Because of the contradiction, the Federal Communications Commission sent letters to both companies as well as AT&T, the iPhone's exclusive carrier, requesting explanations. Google Voice assigns a new phone number to a user, who can then connect home, mobile and work numbers to the free service. Google Voice gives a united voice mail, SMS interface where contacts call the GV number to access all of the user's phone lines, at the user's discretion. For more details, visit the Google Voice information page .

Apple's August response letter says that the Cupertino-based company has not rejected the application, but continues to study it. According to the letter, it appears to replace Apple's own calling application, SMS and Voicemail interfaces with separate Google applications. The process of approving or rejecting apps is done only by Apple, without consulting AT&T, according to specified standards.

Google's own response letter from the same period was initially confidential, but since Apple posted its full letter on its own site, Google decided to allow the FCC to post an unredacted version of the letter Friday.

According to this letter, the Google Voice iPhone application allows all GV phone number associated contacts, calls and messages to be used from the handset. The application uses the carrier's data network, and uses the underlying telephone and SMS services.

FCC material said that Google was told of Apple rejection by correspondence with representatives including meetings, telephone calls and emails. Unfortunately, the discrepancies do not seem to be resolved by the response letters.

According to Reuters , issues surrounding Google Voice could create lasting effects in the US telecommunications industry. The FCC's response could help new entrants or hinder their ability to use large carriers phones to offer competing services, cheaper services.