Classic snake game — eat food, grow longer, but don't run into the walls or your own body. How long can you survive?
The snake lives on a 16×16 board. It starts three squares long in the middle, facing right, and moves one square every 0.18 seconds — a little over five squares a second. That pace never changes, however long the snake grows. Once it is moving, a snake that keeps heading right hits the wall on its eighth step, just under a second and a half later, so plan your first turn early.
Swipe up, down, left or right anywhere on the game area; arrow keys work on a keyboard. A swipe is read when your finger lifts, and movements shorter than 24 pixels are ignored. You cannot reverse straight back into your own neck — a swipe in the opposite direction simply does nothing.
A turn takes effect on the snake's next step, and only one turn is applied per step: if you swipe twice within the same 0.18 seconds, only the later valid swipe counts. To make a U-turn into the next lane, swipe sideways, let the snake take one step, then swipe the opposite way to your original direction.
Each apple is worth 1 point and adds one square to the snake, and a new apple appears at once on a random empty square. Running into a wall or into your own body ends the game — with one exception: the square your tail is just leaving is free, so you may move into it on the same step.
The board has 256 squares, so the highest possible score is 253; fill every square and the game ends with "You filled it!". This device remembers your best score, and after a game over any score above zero can be submitted to the Hall of Fame (top 10). If you switch to another tab or app, the snake freezes and starts moving again the moment you come back.
The snake never really gets harder — your own body does. The single habit that extends a run is to travel in tight lanes and turn at the very edges of the board, leaving the centre open for when the food appears somewhere awkward. Players who wander through the middle quickly box themselves in once the tail grows past a dozen segments.
Once you are long, stop chasing food in a straight line and start thinking about where the tail will be two turns from now. A reliable pattern is to sweep the board in rows like mowing a lawn, so the tail trails neatly behind you and you almost never cross your own path. When food lands in a tight spot, it is usually safer to take the long way around than to dive in and trap your head.
The board's even size hides a perfect route. Because it is 16 squares on each side, there is a closed loop that visits every square exactly once: go up the leftmost column, then weave right and left across the other fifteen columns one row at a time, and the zigzag finishes right next to where it began. A snake that follows this loop can never crash at any length, which makes it the surest way to the full 253. The catch is time: one lap is 256 steps, about 46 seconds, and riding the loop from the first apple to the last takes close to 50 minutes. Strong runs cut straight across the board while the snake is short and settle onto the loop only once it covers a large share of the squares.
Most crashes with a long snake are input slips rather than bad plans. Because a swipe only counts when your finger lifts, use short, quick flicks instead of long drags — a slow drag turns the snake late. Never fire both halves of a U-turn in one motion: if the two flicks land inside the same step, the second one is thrown away and the snake carries straight on in the first direction, often into a wall or its own body. Flick, watch the head move one square, then flick again.