Microsoft is today opening up Windows 10 S to developers by allowing them to test the new version of Windows 10 for free (as long as you are subscribed to MSDN). The company is today releasing the official ISOs for Windows 10 S on MSDN today, which can be used by developers to try their apps out on Windows 10 S.
Using the ISO, developers can setup a virtual machine or even install the OS on an actual hardware if they’d prefer. After the installation is done, they can ensure their apps are working as expected on Windows 10 S. Microsoft provided the different Group Policy policies for Windows 10 S that allowed developers to test their apps against some of the restrictions in Windows 10 S, but that really didn’t give developers all the information they needed to debug an app.
Users with MSDN subscriptions can download the official ISOs for Windows 10 S right here.