Mixing fluids has seldom been more fun than in Tobias Neukom's new iPad 2 or 3 puzzler LiquidSketch. Seldom have those fluids been so carefully modeled, too.

The main game is split into 6 stages with 15 puzzles in each. Players must mix colors, navigate mazes and solve physics puzzles by controlling the liquid. This liquid moves by using the gyroscope, by splashing it around with a flick or by placing pumps and blocks to construct bridges, dams, and fountains. The last two stages (30 puzzles) combine all these mechanics for even greater challenges.

A sandbox mode allows players to experiment with every mechanic, and it is just short of being a functional level editor, sans sharing. There's no goal to it, just chaos.

Speaking briefly with the creator, chaos seems to be the overall essence of the water simulation he's providing. "[I]t's very different from what computers normally do, very continuous and chaotic."

LiquidSketch only became frustratingly chaotic for me when I had to place some blocks on a tiny grid. Neukom responded, "The grid size is a compromise unfortunately. The square size is coupled to the simulation, if I make it bigger the water would look less detailed. I could combine 4 squares into one, but then it would be too big. It probably isn't optimal for everyone. I tried to avoid making a lot of puzzles where accurate placement is required though."

LuquidSketch's puzzles capture a feeling of fluidity that is different than the smoothed particle hydrodynamics found in most water-physics games, as addressed in this paper. Fortunately, one need not read it to enjoy LiquidSketch, available now on iTunes for $1.99.