The technical preview for Windows 10 on smartphones is available beginning today, according to Microsoft employees. 'Okay, Windows Insiders, you've all been patient enough. Today is the day for Win10 Technical Preview for phones,' tweeted Gabriel Aul. Aul's comments were echoed by Microsoft's Joe Belfiore. He said, 'Who's ready!? Who's ready!? Now remember, these bits are early! Still lots of work to do, but still, this will be fun.' In order to access the technical preview of Windows 10 for phones, interested parties will need to be part of the Windows Insider program (free to join). According to the documentation available through Windows Insider, the Lumia 630, 635, 636, 638, 730, and Lumia 830 are compatible with the technical preview. At the moment, Microsoft's flagship handsets, the Lumia 1520 and Lumia 930, cannot install the Windows 10 preview. Owners of these handsets will need to have the Windows Insider app installed on their phone before they can proceed. Microsoft's Belfiore said the company will add features and more handsets to the technical preview over time. The Technical Preview is not for everyday people. It is an unfinished version of the operating system meant for testing purposes. Microsoft isn't expected to deliver the final version of Windows 10 to PCs, tablets, and smartphones until the summer months.