Did I miss the announcement? When did Android's app store, Google Play, hit the 15 million download mark?
According to Google's response to TechCrunch, it happened "a few weeks ago".
Formerly known as the Android Market, Google's last announced its app market was at 11 billion downloads during its Q4 2011 earnings report in January. Doing the math, Google is seeing about 1 billion downloads of Android apps per month.
Apple, on the other hand, is seeing about 1.25 billion app downloads per month. Apple's most recently recognized achievement was 25 billion downloads back in March 2012.
So while Google and Android remain behind Apple and the App Store, perhaps the growing rate of Android activations could eventually help the platform catch up.