BT has launched SmartTalk, a free app which enables users to make calls on their iPhone at the price of a landline call.

Up to five users can register to a single BT account, and use the OTT app to make mobile calls, over a data connection, which are then billed to their home phone calling plan, and charged accordingly.

This means that calls from abroad made via the app will be treated as UK calls, which could potentially make it free – as long as the user is connected to wi-fi and not using up roaming data to make the call.

SmartTalk also provides another solution to the issue of calling 0800, 0845, and 0870 numbers from a mobile, which can charge as much as 50p per minute despite being free for landline callers.

Over the last year or two, a number of parties have launched mobile-friendly voice shortcodes, but that solution requires brands to take responsibility for setting up shortcodes. While the SmartTalk app is essentially a work-around, it puts this power in the hands of customers.

“This is a really exciting breakthrough that means you can take your BT calling plan with you and continue saving money when you’re away from home, either in the UK or abroad,” said John Petter, managing director of BT Retails consumer division. “BT SmartTalk helps you get even more value from your BT package and much more from your smartphone. At last you can actually call freephone 0800 numbers for free from mobiles and get inclusive 0845 and 0870 calls too. And of course, you can take advantage of BT wi-fi which gives you access to a massive network of 7.5m hotspots around the world.”