how to play link up
Link up is a free daily connect-the-dots pipe puzzle. Each color appears as a pair of dots. Draw a pipe between every pair, but pipes can't cross or branch, and when you're done every square on the board has to be part of a pipe. Each board has exactly one solution, so you can always work it out without guessing.
- Drag from a dot to draw its pipe through the squares, up, down, left or right. A soft circle under your finger shows where the pipe is going.
- Reach the matching dot to link the pair. Linked dots get a ring and their squares light up.
- Drawing across another pipe cuts it. Back off in the same drag and the other pipe grows back.
- Tap a dot to start its pipe over, or drag from the middle of a pipe to redraw it from there.
- Link every pair and fill every square to stop the clock. Stuck? A hint lays one pipe of the answer for 15 seconds.
Keyboard: Focus the board, then use the arrow keys to move the cursor. Space or Enter on a dot or pipe picks it up, the arrows then draw (stepping back undoes a square), and Space or Enter lets go. Backspace steps back, Z undoes, H gives a hint, and Esc goes back to the menu.
tips
- Pairs that sit next to a wall or in a corner usually have only one sensible route. Start there.
- If a square has only one way in, the pipe that reaches it has to go through it.
- Long pipes fill the gaps. When every pair is linked but squares are left, a pipe needs a detour.
- One drag per pair is a perfect solve. Every time you go back to a pipe you already drew, it counts as another move.
- Turn on abc if some colors look alike: every dot gets its pair's letter.
faq
Is there always one solution?
Yes. A counter walks every board square by square and keeps it only if exactly one way to fill it exists. Every daily for a year and every practice board is checked that way, and a second, separately written solver re-checks a sample.
What do the levels mean?
Easy is 5 by 5 with 4 or 5 pairs, normal is 7 by 7 with 6 to 8 pairs, and hard is 8 by 8 with 7 to 9 pairs and longer pipes. The daily is normal and the same for everyone.
How is it scored?
By time, from the moment the board appears until every pair is linked and every square is filled, plus 15 seconds per hint. The clock pauses while the tab is hidden. Your moves are counted too: one per pair is perfect.
What does a hint do?
It lays one pipe exactly where the answer has it, cutting anything in the way. If one of your pipes runs through squares that belong to another pair, the hint fixes that first.