Yes — most versions include an undo button, usually available an unlimited number of times.

What makes a move impossible?

You can't move a drop if the destination tube is full or if the top colour of the destination doesn't match your drop.

Is there a time limit?

Drop Sort is not timed — you can take as long as needed to find the solution.

Drop Sort

Drop Sort is a colour-sorting puzzle where you arrange liquid drops across tubes so each tube contains only one colour. The mechanic that makes it more than a pure logic puzzle is the tube-capacity constraint: you can only move a drop if there's space in the destination tube, which means temporary wrong moves are sometimes necessary to unblock the correct sequence.

Tap a tube to select the top drop, then tap another tube to move it there. You can only move a drop onto the same colour or into an empty slot. Moves are unlimited but the puzzle has a minimum-move solution — finding it is the skill challenge. The game shows the tube states as a read-only preview of your next two possible moves.

Works for players who enjoy colour-sorting puzzle games with moderate depth. One puzzle runs 3-8 minutes. Tip: identify which tube is closest to being completed and work backwards from it — protecting one complete tube from disruption usually unlocks the rest of the board faster than trying to solve all tubes simultaneously.

FAQ

Can I undo a move?: Yes — most versions include an undo button, usually available an unlimited number of times.
What makes a move impossible?: You can't move a drop if the destination tube is full or if the top colour of the destination doesn't match your drop.
Is there a time limit?: Drop Sort is not timed — you can take as long as needed to find the solution.