It’s been six years since Apple first unleashed its App Store onto the world and to celebrate several popular paid apps are going on sale for a limited time. As MacRumors documents, you can now get popular apps such as Monument Valley, Threes!, Lost Toys and Drafts for iPad at big discounts of between 50% and 80%. MacRumors also directs our attention to AppShopper’s big list of discounts that will give you a comprehensive look at which apps are getting their prices cut and for how long. In the six years since its launch, the App Store has paid out more than $15 billion to developers and has served as the blueprint for other app stores such as Google Play. We can’t think of a better way to celebrate its birthday by getting some super-cheap apps of our own.