On the eve of the next Apple iPhone launch, a Google executive reminded tech enthusiasts that it is Android, and not Apple’s device, that rules the smartphone world: More than 500 million Android devices have now been activated worldwide, Google Director of Product Management Android Hugo Barra revealed.

“Today is a big day for Android,” he said via Google+, the online advertising giant’s social networking service. “500 million devices activated globally, and [more than] 1.3 million added every single day.”

Those numbers are impressive in their own right, but what’s astonishing is that both represent huge leaps over the numbers Google provided in June at its I/O Conference. At that time, the firm noted that more than 400 million Android devices had been activated, and that activations were occurring at a pace of 900,000 per day.

Much of these gains can be attributed to Samsung, which is both the biggest seller of Android handsets and the biggest smartphone maker in the world. Samsung has already sold more than 20 million units of its latest smartphone, the Galaxy S III—a rate of sale three times higher than its previous bestseller. The Galaxy S III sells more than 200,000 units per day, Samsung claims.

Although Google’s Android OS has been maligned by critics for fragmentation problems—where multiple versions of the system are out in the wild on devices that can't or won't be upgraded by wireless carriers or device makers—Google reports that newer versions are starting to make headway. According to the firm, about 22 percent of all Android devices are now running Android 4.0 or 4.1, the most recent versions of Android. Google’s recently released Nexus 7 tablet and the coming Amazon Kindle Fire HD tablets both run Android 4.1, for example.

Android is expected to once again meet its temporary match when the iPhone 5 goes on sale in the coming days. Analysts predict that Apple could sell as many as 8 million or 10 million iPhone 5s at launch.