Which gaming platform's digital storefront first exceeded $1 billion in annual revenue, revolutionizing how games are purchased and distributed?

In the evolving landscape of gaming and virtual worlds, retail innovations have created entirely new economies and shopping experiences. From in-game purchases to virtual storefronts, gaming platforms have revolutionized how digital goods are marketed and sold. This trivia question focuses on a groundbreaking retail innovation that transformed the gaming industry's approach to digital distribution and commerce.

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Steam (Valve Corporation, 2003)
Xbox Live Marketplace (Microsoft, 2005)
PlayStation Store (Sony, 2006)
App Store (Apple, 2008)