Microsoft confirmed yesterday that the next version of Windows 10 will include an ebookstore and reading app built into the Edge web browser.
With the Creators Update, we’ve added new features like advanced tab management to help you find, organize and open tabs you’ve set aside without leaving the page you’re on. You can now discover and get your favorite e-books in Windows Store and read them in Microsoft Edge across all of your Windows 10 devices.
The Creator Update will be released on 11 April, but that is really all we know for certain at this time.
The store, on the other hand, was spotted in the code in a January beta release of Windows 110 mobile. It didn't work at that time, but we did get a screenshot of the storefront:
Whether the store uses this layout remains to be seen.