Microsoft hit an important milestone on Tuesday as it passed 100,000 Windows 8, Windows Phone 8 and Windows RT apps available on its Windows Store. The app milestone, which the company announced on its official Windows App Builders Twitter account, is important for Microsoft as it tries to catch up with the vast number of apps offered by iOS and Android, which each have more than 800,000 apps available on their respective stores. Microsoft has been very aggressive about using every resource at its disposal to recruit app developers, including paying developers up to $100,000 to bring their applications over to the Windows Phone 8 platform.