The number of text messages sent in Ireland fell by almost 28% in the final three months of last year compared with the same period of 2012, according to the Communications Regulator.

Close to 3 billion SMSs were sent in Ireland between October and December 2012 – however this fell to around 2.15 billion in the last three months of 2013, according to the data.

The sharp decline is likely in part due to the rise of data-based messaging services like WhatsApp, Viber and iMessage, which allows users to send text messages over the internet.

As SMS volume declines, the amount of mobile data has increased, with almost 12 petabytes (12.56 million megabytes) being sent over the mobile network during the final three months of 2013.

This is a 43.7% increase on the amount of mobile data in the last quarter of 2012.

While the rise of messaging services has impacted SMS usage, it has not had much impact on the level of voice calls made in the country, which actually rose year-on-year.

There were 2.86 million minutes of talk on Irish mobiles during the last three months of 2013 – up from around 2.7 million in the same period of 2012.

According to ComReg, there were 5.62 million mobile phone subscriptions in Ireland at the end of December – up 0.2% on the previous quarter.

Almost 57% of these subscriptions were on pre-pay contracts, down slightly on the previous year, while bill pay customers accounted for around 43% of them.

Average revenue per user was €27 per month, down €2 on the last quarter of 2012.

Revenue from the average contracted customer was €40.67 per month, while revenue from the average pre-pay customers was €16.50 per month.