The company announced the milestone on Wednesday during a company meeting at its headquarters in Cupertino, Calif., just a day after it reported disappointing iPhone sales in its quarterly report. The sale happened last week, according to a statement from Apple (AAPL).

“iPhone has become one of the most important, world-changing, and successful products in history,” said Apple CEO Tim Cook in a statement. “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.”

“We never set out to make the most, but we’ve always set out to make the best products that make a difference,” Cook added. “Thank you to everyone at Apple for helping change the world every day.”

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Apple’s iconic device, which is often credited for the boom in mobile apps in recent years, was first introduced in 2007. Since then, the company has released at least a new model every year, with multiple sizes in the last couple of years.

On Tuesday, Apple reported earnings for the year’s second quarter. Though it beat analyst expectations for iPhone sales, it was the second quarter in which sales declined.