Apple claims a recently submitted Vonage VoIP application has been delayed due to technical difficulties with the Vonage software, according to Barron's. An Apple spokesperson said there were technical issues with the code Vonage submitted, but did not elaborate on the problems; however, Vonage issued a response to Apple's statement, saying the 'technical problems' were purely cosmetic in nature--related to the labeling of an icon. Vonage also noted that the company has resubmitted the application with the appropriate adjustments.

The pending status of a similar app submitted by Google sparked an FCC investigation into the relationship between Apple and AT&T. The VOIP telephone service provider posted a response to the FCC's questions last week, claiming it has an agreement with AT&T prohibiting the use of applications that use AT&T's cellular service to redirect a TV signal to an iPhone.

"From time to time, AT&T has expressed concerns regarding network efficiency and potential network congestion associated with certain applications, and Apple takes such concerns into consideration," Apple wrote in its public response to the FCC inquiry.

Apple also stated it has approved a number of VoIP applications that use WiFi, such as Skype, Nimbuzz and iCall, but stressed these apps do not utilize the AT&T 3G network.