Apple will let software developers include virtual-currency transactions in their applications, paving the way for new forms of money to appear on iPhones and iPads.

“Apps may facilitate transmission of approved virtual currencies provided that they do so in compliance with all state and federal laws for the territories in which the app functions,” Apple said in an update to its App Store review guidelines.

While Apple didn’t mention bitcoin specifically, its developer terms now allow for certain “approved virtual currencies”, without saying what those were. Apps that use the digital money must comply with state and federal laws wherever they’re designed to work, the terms say. The change signals that Apple is warming up to virtual currencies after previously blocking programs such as Blockchain.info from its App Store.

Bitcoin is the most popular digital currencies, which governments are struggling to determine how to regulate because they exist only as software. “This is a sign that the ecosystem is maturing and gaining credibility,” Bill Lee, an investor in bitcoin wallet BitGo, said. “To be clear, I still think bitcoin is in its infancy as a technology, but its acceptance is becoming more and more mainstream.”

In the week that Apple held its annual WWDC developers' conference, there was some general media disappointment at the lack of new hardware unveiled at the event, particularly as there had been expectations of the firm's foray into wearable technology with an iWatch.

However, Apple chief executive Tim Cook and software-engineering boss Craig Federighi did showcase the firm's new IOS 8 operating system to several thousand developers. They also showed off new features that come with the latest "Yosemite" Mac platform.

Investors are waiting for Cook to keep a promise to create new product categories. Last week, internet services chief Eddy Cue said the pipeline was the best he had seen in more than two decades.

There was, however, strong interest in Apple's plan for its new health platform for sharing information, Healthkit. This will pull together data such as blood pressure and weight now collected by a growing number of healthcare apps on the iPhone or iPad. The company also announced an app, dubbed "Health" that will be an integral part of iOS 8. The company will work in tandem with Nike, a major player in fitness tracking, and the Mayo Clinic on the new feature, which will be included in the latest mobile software. The news follows Samsung Electronics's announcement of its own mobile health-data product.

Apple has one of the most dedicated software communities in the tech industry, with more than nine million registered developers.

Every year, the iPhone maker and rival Google show the latest software enhancements to thousands of prospective developers. Apple described how Yosemite will come with a much-improved internet storage application similar to those provided by Box or Dropbox; how users can pick up calls to iPhones from their Macs; and how Apple devices would sync constantly with each other.

* Apple has posted the keynote speech from WWDC 2014 on its official YouTube channel. – (Reuters/Bloomberg)