Every single kid in school had a Nokia 3210 or similar. And with each iteration of phone, new screens, tech and software were the talk of the town. But one thing stayed constant: your score on Snake.
Even today, there are hundreds of Snake clones on itch.io and similar services (example, where I ended a 118-turn round... beat that!).
Snake is an incredibly simple premise. You start off as a small Snake-like creature, bopping along inside a small box trying not to hit your own tail. Your tail grows as you eat pixel-sized blocks which make you, as a Snake, grow 1-pixel in length. The game gets progressively harder the more successful you are, in essence.
The real trick to Snake was not to treat it as a pixel-eating game, but as a space management game. How you move has to adapt as the Snake grows. Even if you have a pixel to eat on the other side of the map, you might want to take bizarrely long routes along the edge of the screen to get there, so that you don't bump into yourself and end your run.
At 48x84 pixels wide/deep, and very few mechanisms to control the game outside of buttons on a device that might, at any time, need to interrupt the game for a call, the challenge of developing Snake for Nokia wasn't easy.
Developed in C for the 6110 phone initially by Taneli Armanto, Snake was designed to give phone users something to do. And something to do, it certainly did. In 1997 it launched and up until 2007, Nokia owned over 50% of phone markets globally. So arguably, Snake was always one of the world's biggest video games. And a cultural icon in it's own right.
I can't recommend this retrospective & interview enough, not least because it'll flash back memories of the schoolyard.