Pure Kakuro: Cross Sums

Kakuro is a crossword with digits instead of letters and sums instead of
clues.

Every chain of squares has a given sum. Fill in digits so they add up to it.
Digits run from 1 to 9 only, and no digit repeats inside one chain. There are
no other rules. Nothing is guessed and nothing is brute-forced: every puzzle
has exactly one solution, and reasoning always gets you there.

What's inside

Four difficulty levels: Easy, Medium, Hard and Expert. Every puzzle is
verified by a solver — a solution exists, and there is only one.

A Daily puzzle. One a day, the same one for everyone. Solve them back to
back and a streak builds up.

Checking, your way. Have the game only tell you a mistake is there — or have
it show you where.

A timer and statistics: time on each puzzle, puzzles solved, best and
average time per level. The timer can be hidden.

Autosave. Leave in the middle and you come back to the same place, with the
same digits and the same time.

Rules with worked examples inside the app, for anyone opening Kakuro for the
first time.

Light and dark themes.

No sign-up

No account, no email. The app asks for no access to your files, contacts or
camera.

Kakuro is a quiet game. Nothing here rushes you, no lives run out, nothing
has to be collected. There is a grid, there are sums, and there is the
reasoning that leads to the one answer.