Agar.io is a simple multiplayer game from Miniclip in which you control a circular cell in a large arena filled with other players. The idea is to grow by eating small pellets and smaller cells while avoiding larger cells that can eat you. It started as a browser game and became a mobile hit, because the rules can be learned in a few seconds. Each round is unpredictable, since you share the map with real people, and a single mistake can end a long run.

How the game works
You move your finger to steer the cell, and the cell follows. When you eat pellets, you grow slowly. When you eat another player’s cell, you gain a large amount of mass. As you grow, you move more slowly, so there is a trade-off between size and speed. You can split your cell into two to move quickly and catch smaller targets, and you can eject small amounts of mass to feed teammates or to bait others. Green viruses in the arena can burst large cells into pieces, so they are both a danger and a tool.

Modes and customisation
The game offers several modes, including free-for-all, team play and modes with special rules. You can choose a nickname and a skin, which changes how your cell looks. Some skins are earned through play, and others can be bought. Because player names are chosen by users, you may occasionally see inappropriate names, so parents should consider this when children play.

Strategy tips
Start in a quieter area and eat pellets until you reach a safe size. Stay away from much larger cells, and keep an eye on the edge of the screen. When you are large, move slowly and avoid risky splits unless you are sure of a catch. Use viruses to protect yourself when you are small, since a larger cell may avoid them. Try playing in teams if you want a less stressful experience.

Ads, purchases and connection
The game is free to download and includes advertising, and there are optional purchases for cosmetic items and other extras. It requires an internet connection. Because ads can interrupt play, you may want to check the options in the store listing. If a child plays, use device purchase controls and check the age rating.

Online safety
You are playing with strangers, so avoid sharing personal information and use the report features if available. Do not click suspicious links in messages or on websites that promise free in-game items.

Age suitability
There is no gore and the visuals are very simple. The competitive nature can be frustrating, and some players dislike losing a long run in a moment.

Who it suits
It suits casual players who enjoy short, tense rounds and simple rules. It is good for killing a few minutes. Players who want depth, story or progression may find it repetitive.

How it compares
Compared with slither.io, it uses cells instead of a snake and has a more tactical splitting mechanic. Compared with Clash Royale, it is faster and has no deck building.

Our take
Agar.io is a straightforward, tense game that is easy to start. The official store link on this page is the safest way to get it.