A crossword of numbers. Fill every white cell with a digit from 1 to 9 so that each horizontal and vertical run sums exactly to its clue: and no digit repeats within a single run.
How to play
Tap a white cell to select it, then tap a digit on the keypad below. The clue cell to the left of a row shows the across sum; the clue cell above a column shows the down sum. A conflict (red border) means the digit would repeat or exceed the target sum.
Objective
Fill every white cell so that all across and down sums match their clues with no repeated digits in any run.
Strategy tips
Start with the shortest runs: a 2-cell run with clue 3 can only be 1+2, and a run of 3 with clue 6 must be 1+2+3. These constrain surrounding cells immediately.
Use elimination: if a run of 2 sums to 17, the only possibility is 8+9. Write these "forced pairs" in your head before placing anything.
When a cell sits at the intersection of an across and a down run, it must satisfy both simultaneously. Solve the more constrained run first to find which digits can actually fit.