The number of devices running on Apple, Inc.’s (NASDAQ:AAPL) iOS mobile operating system keeps increasing with each passing release, and according to a new report from Asymco’s Horace Dediu, there may be one billion or more iOS consumer electronics devices sold by the latter part of 2014 to 2015.

Dediu, who acknowledged that his forecast may not be one hundred percent accurate, released his findings yesterday, which were based on the growth of Apple’s iTunes service.

Specifically, the calculations were influenced by Apple’s announcement last Wednesday that there are 435 million active iTunes users at the present. As Apple adds about 12 million new accounts on iTunes each month, which is parallel to the growth in iOS platform usage, Dediu came to the above conclusion of about a billion iOS devices sold by late 2014-2015.

The devices running on Apple’s mobile operating system (OS) include the iPhone smartphone, iPad tablet computer and iPod touch media player.

The number of iOS devices sold at the end of Apple’s June quarter numbered over 400 million, according Apple’s Chief Executive Timothy D. Cook, who spoke at the iPhone 5 launch event last Wednesday, September 12. Mr. Cook started counting from the middle part of 2007, when Apple launched its first-generation iPhone.

Dediu’s forecast would have the number of iOS-powered consumer electronics devices at a level more than twice the present-day number in about two to three years’ time, if proven accurate.