Earlier this year, Sony released a game for iOS and Android called "PlayStation All-Stars Island." Unrelated to the similarly-named fighting game, it was a free-to-play app that was co-marketed by Coke Zero. However, that was just a sign of things to come.

Sony Computer Entertainment Worldwide Studios president Shuhei Yoshida explained that Sony has "totally shifted our way of thinking." Whereas the notion of an official PlayStation-branded app would've been impossible not too long ago, Yoshida says that the company is now actively developing games for mobile platforms.

"We're creating small games that go with PS4 titles," Yoshida told GI.biz. For example, "we're releasing a puzzle game themed around Knack that you can play for free. It's fun, and by playing the game you earn some items that you can use on PS4."

Yoshida explains that mobile phones cannot be viewed as "competition" to Sony's gaming platforms, pointing to how everyone has a PC--and that doesn't stop people from buying consoles. "It's like everyone had a PC before--it's a tool that people use every day. Why not try to include them in the PlayStation ecosystem?"

By releasing games and apps on mobile devices, Sony believes it will be able to increase its reach. "Even if you don't own a PS4, it can be a way to find out what's happening in the PlayStation world," Yoshida said. Specifically referring to the Knack mobile game, he said: "People might be motivated, because they've already unlocked some items, to take a look at what this Knack game on the PS4 is all about."