"While this is encouraging, it again also raises issues for operating within a regulatory framework built on many traditional fixed line telephony assumptions."

The number of wireless broadband services has exceeded 2.1 million following last year's spike, but fixed line telephone services fell by three per cent to 10.7 million over the same period.

The also found mobile phone services ballooned by almost four million to 12.28 million due to next-generation handsets and new data-intensive services, while revenue from mobile networks exceeded those of fixed line services.

also increased last year by some 54 per cent, according to the Telecommunications Industry Ombudsman (TIO).

In the TIO's annual report, the Ombudsman, Deirdre O'Donnell, called for the industry to pick up its game as the level of complaints around customer service were still "unacceptably high".