Microsoft provides a list of phones that support the preview program here.Microsoft supports a wide variety of Microsoft Lumia (formerly Nokia Lumia) phones.The phased Windows 10 creators update rollout plan for PCs and tablets also will be Microsoft's approach with its Windows 10 Mobile creators update release, starting on April 25.
For years, the Windows Insider Preview Program has let Windows phone users get the latest Windows operating system for their phones without requiring the approval of any cellular carrier.
The Insider Program lets you upgrade to Windows 10 and immediately jump off the preview builds, sticking to the stable builds.
The Windows 10 Mobile "creators update" operating system will be arriving for Windows Phone devices, starting on April 25, Microsoft announced today.
Yesterday, Microsoft noted that the general rollout of the "current branch" of the Windows 10 creators update (version 1703) would start to arrive on April 11, but its mobile OS rollout plans for Windows Phone devices weren't specifically mentioned until today.
Microsoft's announcement today also explained that the general rollout of the creators update for PCs and tablets will happen gradually.