Apple doesn't want you to notice all those headlines about weak iPhone sales.

One day after posting its third quarter results, in which it revealed iPhone sales have continued to decline, Apple announced that it recently sold its one-billionth iPhone. Apple CEO Tim Cook said this about the major milestone:

"iPhone has become one of the most important, world-changing and successful products in history. It's become more than a constant companion. iPhone is truly an essential part of our daily life and enables much of what we do throughout the day. Last week we passed another major milestone when we sold the billionth iPhone. We never set out to make the most, but we’ve always set out to make the best products that make a difference. Thank you to everyone at Apple for helping change the world every day."

Despite this news, research firm Consumer Intelligence Research Partners said people are waiting longer to upgrade to the newest iPhone. Nearly half of iPhone owners now wait until their device is two years or older to upgrade. But in 2013, only 34 per cent of iPhone owners would wait.

This is clearly affecting Apple, as iPhone sales have been falling. It even led to the company posting its first quarterly revenue drop in 13 years last quarter. Then, on 26 July, Apple posted third quarter results, revealing that iPhones sales dipped again - 21 per cent from the year-ago quarter.

The iPhone debuted in 2007. Apple has released nine models of the device since then, and it will celebrate the 10th anniversary of the iPhone next year. It's rumoured to have something significant planned for that year's iPhone, including maybe a dramatic design change with a glass body, edge-to-edge display, among other things. It might even ditch the home button.