How the jigsaw works
The picture is cut into curved pieces with tabs and blanks, like a cardboard puzzle. The pieces start scattered on the table around the board. Drag one onto another: if they are true neighbours and you drop them close enough, they snap together with a soft click and from then on move as a group. When a piece or group lands close to its home on the board, it locks there.
There are no wrong snaps. Two pieces only join when they really belong together, so a click always means progress. Undo takes back the last move, or several in a row, if you change your mind.
Tools on the bar
Edges hides everything except the border pieces, which is the classic way to begin. Sort tidies the loose pieces into rows around the board, border pieces nearest — useful after the frame is done, or after you turn your phone. The ghost button lays a pale version of the picture underneath the pieces, and the preview button opens the full picture in a corner. The hint flashes one loose piece together with the neighbour it fits.
Choosing a size
The size buttons ask for 24, 48, 100, 150 or 200 pieces. Because the pictures are wider than they are tall, the cut keeps every piece nearly square, which is why the real counts are 24, 48, 96, 150 and 198. On a phone, 48 pieces is the default and anything up to 96 stays comfortable; the larger sizes are best with a mouse or a tablet, though zoom makes them playable anywhere.
The picture matters as much as the count. A scene full of detail, like a tide pool crowded with sea stars, gives every piece something to recognise. A scene with a lot of open blue water or pale sand is slower, because those pieces all look alike and you have to match them by shape.
A reliable order of work
Build the frame first. Then work outwards from the strongest feature in the picture — an eye, a shell, a lighthouse — because those pieces are easy to place by colour. Leave the plain areas for last. By then only a few pieces are left, and the shapes of the empty gaps tell you where they go.
If you like a challenge, turn the ghost and preview off and try to finish without hints. Your best time for each size is kept, and the numbered dives add fixed puzzles that everyone plays with the same cut.
Questions
Is my puzzle saved if I close the tab?
Yes. The position of every piece is saved in this browser after each move. Come back to that picture with the same piece count and you carry on from where you stopped.
Can two pieces join in the wrong place?
No. Pieces only snap to their real neighbours, so every join is correct. A loose piece dropped in the wrong spot simply stays loose.
How do I zoom on a phone?
Pinch with two fingers or double-tap the table. The plus, minus and fit buttons in the corner do the same.
Why does the 100 button give 96 pieces?
The pictures are 3 : 2, so a 12 × 8 grid keeps the pieces almost square. That gives 96 pieces, close to the 100 you asked for.