Microsoft has just released the latest PC preview version of Windows 10, build 10166. The major ordeal here in build 10166 is the inclusion of the Microsoft Wi-Fi app. The build is about bug fixing, fit and finish.
Gabriel Aul, head of Windows Insider explains that this build is only being offered to users who have Windows Phone 8.1 installed on their phone and are on the Windows Insider Fast ring. He also states:
With Windows 10, we are giving people the ability to purchase paid Wi-Fi through the Windows Store via the Microsoft Wi-Fi app. You will know when you can purchase Wi-Fi when you see “Buy Wi-Fi from Windows Store” in your list of networks when clicking on the network icon on the lower right in the Taskbar. The Microsoft Wi-Fi app provides the choice to pay with a Credit or Debit Card, a Microsoft Gift Card, PayPal, or Wireless Carrier Billing, and it helps keep your information secure since it uses the Windows Store payment system.
There is also an updated Windows 10 SDK preview release with this build. If you are not enrolled in the Windows Insider Program, sign up for it here.