In early March, Epic Games boss Tim Sweeney accused Microsoft of trying to monopolize PC game development with Windows 10. Xbox boss Phil Spencer commented on the accusation while talking to press after Microsoft's Build conference, saying you don't have to sell your game or app in Microsoft's store to be a Universal Windows Application.

　　"You have to submit to our store if you're going to sell through our store, but you don't have to sell through our store," he explained.

　　"With Xbox, I've got five-year-olds through 95-year-olds on my platform and I need to know that my parental control systems are going to work, I need to know that IP protection is there. I can't have somebody ripping off Mario 64 and throwing it in our store," Spencer said. "I will protect the sanctity and safety of the Xbox One experience because as a parent myself I want to know that when I say 'This is what my kids can see or play,' this is what's going to happen... Beyond that, I'd love to see a ton of applications come to Xbox and games obviously."

　　He also talked about how Windows' success "has been based on anybody being able to write a game," using Minecraft as an example.

　　"Notch wrote this Java game, stuck it on a website, put a Paypal link next to it, said 'Click here to download,' and now he's a billionare," he explained. "There aren't that many ecosystems out there where something like that can happen."

　　Spencer added that "if you have the device driver, you can plug anything into a PC" as it's always been "an open ecosystem.

　　"What Tim wanted us to say is 'We're not locking down the app framework to lock down people's ability to distribute games and applications on the platform,'" he said. "That's right, that's not what we're doing."

　　Spencer spoke at the Build keynote to talk about how Microsoft is making Windows 10 a "great gaming experience." The keynote also brought the announcement that all future Forza games will make their way to PC in addition to Xbox.