Microsoft (NSDQ: MSFT) has announced a “Mobile Incubation Week” in April in Silicon Valley, followed by events in Europe and Asia. The event is free and companies can send up to 3 people, with the intent being to foster development on the Windows Mobile 6.1 or 6.5 platforms. There are more than 20,000 apps for Windows Mobile, but they’re scattered over several stores—something Microsoft hopes to fix with Windows Marketplace For Mobiles. Apple (NSDQ: AAPL) just passed the 25,000 mark in apps for its iPhone, meaning it now has more total apps that Windows Mobile does—something Microsoft probably wants to change.