Atom Bank, a U.K.-based mobile-only institution, has announced that regulatory restriction has been lifted and it is now open for business.

Atom launches with a mobile app that offers a competitive fixed-term savings account, according to a press release. The app will be made available to all iPhone and iPad users who have preregistered their interest through the Atom website. An Android version will follow shortly, the FI said.

Atom also will offer secured lending to SME businesses through a number of specialist business intermediaries, according to the announcement.

Atom plans to unveil additional products and continuous app enhancements, with a phased rollout of services throughout the year. By the end of 2016, customers will have access to fixed-term savings, current accounts, overdrafts, debit and credit cards, instant access savings and residential mortgages, all serviced via the app. 

"The team has achieved something that simply hasn't been done before," said Atom Bank Founder and Chairman Anthony Thomson. "We believe we have built a bank in record time, and we're not planning to stop here. It is not a simple task, and having an amazing team working hard to deliver the seemingly impossible has been crucial. We are all fully committed to continuing to innovate and deliver a transparent way of banking that turns the old world on its head."