Apple CEO Tim Cook spoke briefly about the upcoming Apple Watch during a call with analysts to say the smartwatch will go on sale before the end of April.

Speaking after Apple posted first-quarter earnings of $18 billion (£11.8bn) - the highest in global corporate history - Cook said he is "using the Apple Watch every day" and "cannot live without it."

But more importantly, and addressing Apple's previous claims of an "early 2015" release date, Cook said the Watch is on schedule. "We look at the year and say early is the first four to us it's within the range...we're going to be thrilled to start shipping it."

Cook also said that interest from developers creating application for the Watch has been "impressive" and the company is seeing "incredible innovation coming out" from Watch developers.

Announced at a media event in September and alongside the iPhone 6 and 6 Plus, the Apple Watch marks the California company's first step into the growing smartwatch industry, currently dominated by Google and its Android Wear operating system.

The Watch will come in two sizes and although Apple says prices will start at $349