Microsoft has updated their Microsoft by the Numbers site, and have announced a new number for the number of apps in their ecosystem.
Unlike previously when they broke them out, Microsoft has now combined the Windows Phone Store and Windows 8 store numbers, with the total now coming to 525,000 apps.
This is up from 400,000 on the 27/6/2014, when Microsoft announced 245,000 Windows Phone and 155,000 Windows 8 apps. Microsoft later updated the Windows Phone numbers to 300,000 in August 2014.
In some ways combining the numbers obfuscate the real growth of both platforms, but with Windows 10 the stores will presumably be combined in reality, which would make the number more relevant.
Competing platforms Android and iOS have around 1.3 million apps in their respective stores.
See the full Microsoft by the numbers PDF here.