Kolba

Kolba is a calm ball sort puzzle. One new puzzle every day, the same one for everyone, plus as many extra boards as you like.

Move balls between glass tubes until every colour sits in a tube of its own. A group of the same colour on top moves together. Some puzzles add a jar: it holds one group at a time, locks to the first colour you put in it, and has to be empty when you finish. That one rule changes how you plan.

A journey from an atom to the universe: behind your tubes, each run of 20 chapters is one step up in scale. You start inside an atom, pass molecules, cells, a leaf, a meadow and a forest, rise above the clouds, circle the Earth and the Moon, and sort your way out to the stars, a galaxy and the whole universe. Tilt your phone and the world slides gently behind the board.

• 300 numbered chapters: finish one and the next is a tap away, from three colours up to eight • Soft music, off in Settings • A new daily puzzle at midnight, the same for everyone, easiest on Monday • Free play at the size you choose: easy, like today, or hard • A short tutorial that teaches by playing, not by reading • Hints that nudge before they tell, and undo as far back as you like • A score from your moves against par, with no timer on the daily • A quiet month view of the days you played, with no streak to lose • Ball palettes and backgrounds to suit your eyes • Colour-assist symbols, high contrast, reduced motion and VoiceOver support • Optional Game Center leaderboards and achievements • Optional iCloud sync of your lessons and finished days • A widget, a Control Center control and a Siri shortcut for today's puzzle • In English, Turkish, Spanish, Portuguese, French, German, Hindi, Russian and Indonesian

No ads. No purchases. No account. No tracking. Kolba works fully offline. Nothing goes to us: iCloud sync goes to your own iCloud, Game Center only if you turn it on.

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