Tiffin carts in different colours leave the cafe kitchen at the bottom of the screen and roll along a little rail network to the houses at the top. Every house has a colour and a shape, and every cart carries the same colour and shape as the house it belongs to. Tap a junction to flip its switch: the arrow and the glowing rail show which way the next cart will go. Flip a switch after one cart passes and before the next one gets there. Each level sends a set number of carts; a cart that reaches the wrong house costs one of your 3 tries. Early levels have two or three houses and slow carts; later levels have up to seven colours, faster carts, more carts on the rails at once and longer routes. A chai break slows the carts down for a few seconds once per level. Sharpness for fun.