A calm colour puzzle for your phone. You get a row of glass tubes filled with mixed coloured balls. Tap one tube, tap another, and move the balls until every tube holds a single colour. That is all there is to it.

HOW YOU PLAY
Tap, do not drag. One finger is enough.
Balls of the same colour stacked on top of each other move together.
Made a bad move? Undo it. As often as you like.

NO RUSH, NO PENALTY
There is no timer and there are no lives. You cannot lose.
Undo is free and unlimited, all the way back to the start of the level.
Restart is always there and costs nothing.
You will never get an ad in the middle of a puzzle.

IF COLOURS ARE HARD FOR YOU
Turn on colour blind mode in the settings. Every colour then gets its own symbol on the ball: a ring, a triangle, a square, a diamond, a plus, a cross, a dash. You play by shape instead of by colour.

300 LEVELS, ALL SOLVABLE
Level 1 has three colours and five tubes. Level 300 has eight colours and ten tubes. In between it builds up quietly.
All 300 levels were checked in advance and can be solved without help. You never have to buy anything to move on.

HELP IF YOU WANT IT
Hint: shows the next sensible move. You still make it yourself.
Extra tube: one more empty tube for the rest of this level.
Both are paid for with coins you earn by playing.

IN THIS VERSION
No ads.
No in-app purchases.
No internet connection needed. The app does not even ask for that permission.
No account, no sign-in, no email address.
Your progress stays on your own device.

WHO IT IS FOR
For adults who like quiet puzzles. In a queue, on the sofa, or when you want to think about nothing for a while.

ALSO GOOD TO KNOW
Works offline, on a plane and underground.
Remembers a half finished level: close the app and you come back to it.
Sound can be turned off.