It has taken 25 days to go from 50,000 to 60,000 items, compared to 40 days to go from 40,000 to 50,000. At the time of writing, 61,479 items have been published. Of these, 24,951 were added in the last 90 days and 11,935 were added in the last 30 days. These items come from 15,173 different publishers.
Growth of Windows Phone Marketplace. Figures up to January 21st.
In the last complete week (January 8th to January 15th) 3,362 items were added to the Marketplace. This compares with 405 items for the same week last year. This would suggest Windows Phone prospects, in app terms at least, are looking much healthier for 2012, than they did for 2011.
It's worth stressing that the quantity of apps is best used only as a guideline metric. The quality of apps in an app store is also very important, but is more difficult to judge objectively.
Looking at how many times an app has been rated can provide some guidance here, as only applications and games seen as useful are likely to be downloaded and rated multiple times. In the Windows Phone Marketplace 4,052 apps have been rated 5 or more times.
Additions to the Windows Phone Marketplace (note numbers for week 3 not complete)
These numbers are from our own tracking system, which is also used to power the All About Windows Phone Apps & Games section, where you can browse all of the applications and games, and install them via links to Zune Desktop, the web-based Marketplace, or install them directly by scanning the QR Code with Bing Vision on your smartphone.
If you're interested in getting additional insight or more detailed data, please get in touch and ask about the AAWP App Tracking service.