My One Color was an experimental iOS app I designed and built in 2013. It simply gave everyone who downloaded it one and only one of the 16.7 million RGB (Red/Green/Blue) colors the world has to offer, and made sure that no two people ever got the exact same color. The user would shake the device to spin the "color wheel", tap the screen to cause the wheel to slow down, and eventually they would be assigned a random, but completely unique color in a fan-fare of music and ribbon-like banners.
To make things more interesting, I programmed in a few thousand "special" colors, pulled from online lists from Crayola, Pantone, HTML web colors, and others. If a user was given a special color, they were told the color's name along with a description of the color's greatness. Whether or not the color was special, the user also had the option to give their color a new nickname.
At myonecolor.com, there was an endless, scrolling display of all the colors that users had gotten, along with those users' names and nicknames for their colors. Each color also had its own permalink that could be shared with friends to immediately jump to that color.
Despite being a fairly simple app, there was one particularly interesting technological achievement that came out of it. Each color came with a quirky description, but I obviously didn't want to program in 16.7 million different color descriptions, so I needed a way to auto-generate them. Noticing that HSL color space was more suitable for this than RGB color space, I created an algorithm that converted the color's RGB values to HSL values, and with a little magic, generated human-readable descriptions of the color such as, "dark grayish yellow" or "light magenta".