Slither.io

Slither.io arrived on mobile as a response to the browser hit Agar.io of the time, with which it shares the core principle – the player controls a gradually growing creature on a shared online map full of other real players. Instead of a cell you control a snake that collects glowing pellets, lengthens, and tries to make opponents crash into its body, while it must itself avoid the same fate and watch both its own tail and the surrounding players at once.

Touchscreen controls are based on a simple drag principle – the snake heads wherever your finger points, while a second tap triggers a short speed burst at the cost of body length. This simplicity is also the game's main strength: it needs no tutorial, works on older hardware and slower connections, and a match lasts exactly as long as the player manages to survive among dozens of other snakes on the same map. The atmosphere is deliberately minimalist, the colorful map on a dark background serves purely for orientation, no graphical showiness has a place here, so the player's attention stays where it belongs – on movement and tactics.

The game is free-to-play with ads and cosmetic add-ons for purchase, without any real pay-to-win element affecting the actual gameplay. It was precisely this undemanding monetization combined with simple rules that helped the title keep its player base for years after the initial wave of popularity around .io games.

Why play it: A great choice for quick sessions between other tasks – you'll grasp the rules in a few seconds, and the ads are more of a minor toll than an obstacle.