Microsoft has posted an article detailing how Telltale Games brought Minecraft: Story Mode to Windows 10 via the Windows Store. It also says Telltale is working on bringing the game's engine to Lumia phones running on Windows 10 Mobile.
In a blog post Zac Litton, Telltale's vice-president of Tech, says that the developer separates its game engine from its game creation tools:
Thanks to their architecture, Telltale doesn't need to port each and every episode of Minecraft: Story Mode over to the Universal Windows Platform (UWP) in order to get it into the Windows Store. Instead, they only needed to port the Telltale engine once, and from there, all episodes will run correctly. Based on their code check-in history, Zac estimates that it took a couple of developers only about three months to go from an initial build to getting Minecraft: Story Mode shipping on the new platform.
It also sounds likely that Minecraft Story Mode, and other Telltale games, could be coming to Windows 10 Mobile sooner rather than later:
Currently, Telltale Games is targeting PCs and laptops in the Windows 10 market, but they already have a build of their story engine that could be used for Lumia phones running Windows 10 as well as future Windows 10 devices. Based on their extensive experience with mobile platforms and gaming consoles, the UI changes involved with smaller screens as well as larger screens is easily surmountable now that the technical challenge has been solved.
Litton adds that Telltale does indeed plan to bring all of its back catalog of games to the Windows Store this year. That will include its Walking Dead and Game of Thrones episodic titles, and hopefully its upcoming Batman game.