For those of us who spend a decent chunk of our time playing games on our phones, there’s nothing quite like the irritation of in-game ads. These ads are a hallmark of the freemium model, which allows us to play games for free, but at the cost of enduring a barrage of advertisements. You know the ones—ads with fake countdowns, those pesky “X” buttons that seem to do anything but close the ad, and interactive elements that trick us into opening the app store. However, Valve has made it crystal clear: any attempt to incorporate these tactics on its PC store will be met with an immediate ban. – John Walker