Pour it.
Burn it.
Blast it.
Tumblegrain is a sandbox of 84 materials, parts and tools that heat, melt, flow, grow and explode. Every grain carries its own momentum, so piles slump, water sloshes and blasts throw debris across the screen.
This whole page is a sandbox. Pick a material from the toolbox and pour it anywhere. Words and cards are solid, so grains pile up on them. Tap the headline too.
Eighty-four things to drop
Ten families, from powders and liquids to living things and logic parts. Each square below is one entry in the palette. Seven of them are loose on this page: pick one from the toolbox at the bottom.
Magnetic ink. It flows like oil until a magnet drags it into spiky crowns.
Pulls loose grains and liquids in from far away. Throw sand past it and it goes into orbit.
Paint that shows temperature: blue when cold, green when warm, red when hot.
Heats itself. Pack enough of it together and the pile gets hot enough to melt.
Copies the first material that touches it, then keeps emitting it.
Sucks in air and anything loose nearby, and deletes whatever touches it.
Slowly turns whatever it touches into more of itself. Fire and heat kill it.
The Tumblegrain sprite. Walk, jump, and throw whatever material Pip last touched.
Little sand beetles. They roam, climb, nip at Pip and run from fire.
Grains that carry weight
Most falling-sand games move one cell at a time. Tumblegrain gives every grain a velocity, so things are thrown, carried and splashed.
Momentum
Grains keep their speed. Explosions throw debris, and detonations queue up so a long chain reaction never freezes the game.
Rigid bodies
Boulders roll and sink. Crates slide, stack, float and burn. A blast throws both.
Heat and air
Temperature, pressure and wind are simulated. Oil pools burn from the surface down, and melted metal sets back into metal as it cools. Switch views to see it all.
Logic parts
Switch, inverter, delay, sensor, piston and lamp, plus batteries and copper wire. Build traps, timers and machines.
Rewind
Hold to run time backwards and try a different idea from just before it went wrong.
Stylised look
Water with rolling waves, foam and light caustics, and textured stone, wood and metal. Zoom in and it stays crisp.
Eight puzzles and a daily twist
Each puzzle limits what you can use. All eight have been checked as winnable on both desktop and phone screen sizes.
Special delivery
Get sand into the basket. It has to slide down the ramp.
Lights on
Bridge the gap with copper wire so the battery lights the lamp.
Firefighter
Put the fire out before half the cabin burns down.
Thaw
Melt the deep-frozen ice locked inside a copper box. Copper carries heat well.
Glassworks
Turn sand into glass. Ordinary fire is not hot enough.
Oil spill
Clear the oil floating on the pond without boiling the pond away.
Tripwire
No battery here. Use a sensor to catch the falling sand and light the lamp.
Dam buster
Blast through the concrete dam so the water floods the empty side.
Daily twist
A new seeded variation every day, the same for everyone. Solve it on consecutive days to build a streak.
There is also a codex of 39 discoveries to unlock as you experiment.
Status
Updated 20 October 2026.
Web taster
Fourteen materials in your browser, including lava, lightning, fireworks and a gravity well. Rewind is in there too.
Full game on iPhone, iPad and iPhone Duo
All 84 materials and parts, the challenges, discoveries, autosave and sharing, with haptics, Apple Pencil support and Duo tabletop mode. Everything unlocked for one price.
Game Center and Mac
Game Center support is in place and switches on with a developer account. A Mac version is set up but not yet tested.