Touchscreens have become a universal interface for everyday devices, from microwave ovens to car dashboards. But in the early 2000s, the concept was virtually unheard of. When Apple released the second-generation iPod in 2002, its screen wasn’t touch-sensitive, but it introduced a distinctive touch-sensitive scroll wheel below the display. Users could navigate menus by swiping a finger around the wheel - a fast, intuitive, and even fun control method that set the iPod apart from its competitors. At the time, most MP3 players relied on clunky directional buttons and awkward combinations to perform basic tasks. The iPod’s innovative interface paved the way for Apple’s deeper exploration of touch control. In 2007, Apple released the iPod Touch, featuring a full-sized, fully touch-sensitive display. This allowed for smoother, faster interaction and expanded functionality. More than just a music player, it came preloaded with apps like an alarm clock, calendar, weather updates, and a variety of games. That same year, Apple unveiled its first mobile phone. The combination of the touchscreen interface and app ecosystem of the iPod Touch with the connectivity of a mobile phone, made the iPhone a huge success, selling over 2.3 billion iPhones by 2025 - more than double the total sales of all PlayStations and Harry Potter books combined. Another major factor in the iPhone’s success was carrier support. AT&T, and later other network providers, promoted the device to boost their sales of data packages - essential for downloading the ever-growing library of useful and entertaining apps.