DS
After years of dominating the handheld gaming market with the Game Boy and Game Boy Advance series, Nintendo took things to another level in early 2004 with the release of the Nintendo DS. Originally designed to coexist with the Game Boy Advance (GBA), the DS eventually replaced it outright—thanks in part, to backward compatibility with GBA titles. The DS featured several innovations, including dual LCD screens—one of them being a touchscreen—an onboard microphone, and WiFi capability. A direct competitor to Sony's PlayStation Portable, the DS remained in production through 2013 and featured several iterations, including the DS Lite and DSi. Eventually, it was replaced by the 3DS, which was released in 2011 and was produced until 2020. The DS boasted several popular games—including Castlevania: Dawn of Sorrow, Chrono Trigger, Grand Theft Auto: Chinatown Wars, and the Pokemon series—and sold more than 154 million units worldwide.