A group of US consumer interest groups are set to file a complaint against AT&T, following the operator’s decision to restrict access to the FaceTime app included in Apple devices – including the new iPhone 5. Three bodies are to make filings with the US Federal Communications Commission, arguing that this goes against the principles of “net neutrality”.

According to a letter sent to the operator by Free Press, New America Foundation’s Open Technology Institute, and Public Knowledge, the decision to only offer the service to consumers with its new shared data plans “harms individuals and innovation alike”. It notes that groups affected include “particularly the deaf and hard of hearing, as well as all who use this application to communicate with family and friends over the internet”.

In a blog post last month, the operator argued that it is not going against net neutrality rules, because customers can still download other alternative voice and video apps, and that “the FCC’s net neutrality rules do not regulate the availability to customers of applications that are preloaded on phones”. It said that while FaceTime will remain available over WiFi, it is limiting use over the mobile network “out of an overriding concern for the impact this expansion may have on our network and the overall customer experience”.

It also hinted that a future change of strategy may be possible, in that “we always strive to provide our customers with the services they desire and will incorporate our learnings from the roll-out of FaceTime on our mobile broadband network into our future service offerings”.

The consumer groups noted that the operator’s sharing plans include unlimited voice and text minutes, which a customer may not want. “It’s particularly outrageous that AT&T is requiring this for iPad users, given that this device isn’t even capable of making voice calls”, said Matt Wood, policy director of Free Press.

John Bergmayer, senior staff attorney with Public Knowledge, said: "By blocking FaceTime, AT&T is harming its users and holding back mobile innovation. What’s more, its behaviour is illegal. When the FCC adopted its Open Internet rules, it guaranteed that mobile users would be protected from such behaviour.”

According to a Wall Street Journal report last week, Verizon Wireless and Sprint have said they will not charge more for customers to use FaceTime over mobile networks.

FaceTime had previously only been available via WiFi, but Apple added support for cellular networks to the app as part of its iOS6 release.

Under the FCC’s Open Internet rules, anybody intending to make a complaint needs to give “at least 10 days” notice of their intent to file. Free Press said that it will make its submission to the FCC “in the coming weeks”.