There are no full-screen ads in this game. Not between puzzles,
not on launch, not ever. Ads appear as a small banner at the bottom
and nothing else.
YOU CAN SEE WHAT FITS BEFORE YOU PRESS
Tap a square and the digit buttons appear. Digits that cannot go in
that square are pale and struck through.
Entering a wrong digit by accident is simply not possible.
A PALE DIGIT IS STILL A BUTTON
Press one and the square that is in the way lights up on the board.
Not "7 does not go here" but "there is already a 7 *there*". It points
at the reason, so there is nothing to read and remember.
IT TELLS YOU THE MOMENT THE PUZZLE IS LOST
Some digits break no rule and still leave the board unsolvable. The
worst part of sudoku is noticing the contradiction twenty moves later
and clearing the lot.
You are told as the digit goes in. Take it back and carry on.
THERE IS NO NOTES MODE TO FORGET
The digit buttons open for one square and close again, so there is no
lasting mode you can leave switched on by mistake.
Tapping a square does not write anything either, so a stray tap cannot
wipe a digit you had right.
IF YOU WANT NONE OF THAT
Turn Help off in the settings and the board behaves like paper.
- Write any digit anywhere
- Clashes are shown in red, not prevented
- Nothing warns you that the puzzle is lost
- Notes are available
Only direct clashes along a row, a column or a box are ever greyed
out. Hidden singles, locked candidates and naked pairs are all still
yours to find. The difficulty is not reduced.
54 PUZZLES, 4x4 UP TO 9x9
It does not start at 9x9. Eight 4x4 boards, twelve 6x6, then fourteen
gentle 9x9, twelve regular and eight harder.
Every board has been machine-verified to have exactly one solution.
There is no guessing.
IF COLOURS ARE HARD TO TELL APART
The board and button colours were chosen by measurement, checked
through simulations of protanopia, deuteranopia and tritanopia.
Colour is never the only signal. A digit that cannot fit is struck
through, and the square in the way is outlined.
Text contrast meets the stricter of the international grades, the one
intended for readers with reduced acuity.
Works with no internet connection. No account, no sign-up, no
personal data.
LINKS
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Privacy Policy https://b19.co.jp/privacy-policy/
