Missing Digits vs KEEPYBOO

Guessing won't fill the blanks. Logic will. Follow the carry from the ones column, and every hidden digit narrows to a single answer. Missing-digit arithmetic and classic cryptarithms, in one quiet app. • Free to start. No subscription • No third-party ads • Your records stay on this device ■ Your first puzzle Your first puzzle walks you through it, one column at a time. No need to know the rules. You can replay it anytime from How to Play in Settings. ■ Missing digits Part of a written sum is hidden. Fill in the blanks so the arithmetic works. • Easy: column addition • Normal: addition and single-digit multiplication, chosen so you can't just subtract your way through • Hard: long multiplication with partial products • Oni: 4×3-digit and 5×2-digit long multiplication Puzzles are generated on your device, so you never run out. ■ Cryptarithms Letters stand for digits, as in SEND + MORE = MONEY. Same letter, same digit; different letters, different digits. 119 puzzles built from everyday English words. ■ Exactly one answer Each puzzle starts as a completed sum, and digits are hidden only while a single answer remains. Every cryptarithm was chosen because it has one solution. ■ Today's puzzle and ranks One puzzle a day, the same for everyone. Weekdays are Normal; weekends are Hard long multiplication. Earn points as you solve and climb from 10th Kyu to Master. Your streak and a calendar keep your history visible. ■ Quiet help • Columns that can't work out are gently tinted (you can turn this off) • If you're truly stuck, a hint reveals a single cell ■ Chalk on a blackboard Deep green board, chalk-white digits, set vertically the way you'd write by hand. The board lights up gold when you solve it. On iPhone and iPad, the board grows to fit your screen. ■ Great for • Sudoku and crossword fans who want puzzles that actually use arithmetic • Anyone who'd rather deduce than drill • Kids preparing for entrance exams, and their parents • Building a small daily brain-training habit • Playing on planes and trains with no signal ■ Privacy • No account required • Puzzles are created inside the app; no connection needed to play • No tracking • To show other apps by the same developer, the app reads public App Store listings only. None of your data is sent

Find the ghosts hiding on the board, using nothing but the numbers. Nothing is left to luck. All 2,000 puzzles solve by reasoning, start to finish. When you get stuck, a hint shows you why the next move is forced. ■ The rules A number in a cell counts the ghosts in the eight cells around it. A number at the edge of a row or column counts the ghosts in that line. Mark the cells you've ruled out with an ×. Reveal a cell with no ghost in it and you lose one of three lives. Lose all three and you start the puzzle over — on the spot, nothing else lost. That's everything. The first puzzle teaches you as you play it, so you can start without reading any of this. ■ If you love Sudoku, nonograms or logic grids KEEPYBOO never asks you to guess: the numbers always give you a logical next move. 2,000 puzzles, from gentle to expert, and the first one teaches you how. · One wrong tap doesn't end the board (three lives, as above) · Nothing is a coin flip. Every one of the 2,000 puzzles has been checked to solve by reasoning alone, all the way to the end · Rows and columns have totals too, so you can work the whole board ■ You don't have to be a maths person The 160 EASY puzzles are built entirely from moves where a single number tells you the answer. Higher sets add new kinds of move: comparing two numbers, then assuming a ghost is somewhere and finding the contradiction. The boards grow, but that isn't where the difficulty comes from. Every technique is written up in the Tips library, one at a time, illustrated on a real board. ■ Solve it, and a second puzzle opens Come back to a puzzle you solved by pure deduction and the ghosts now show faintly. The question is no longer where they are, but in what order to catch them. On the same board, the order can change the score several times over. Only the best order earns the diamond. Finish one with no hints and no mistakes and you earn a crown. Every one of the 2,000 puzzles can be solved, and then mastered. ■ 2,000 puzzles, ten sets EASY, NORMAL, HARD, EXPERT and MASTER — 1,110 puzzles — are free. Past those are EXTREME (690) and ULTIMATE (200), and the first several puzzles of each are free to try. A small board takes a few minutes; a large one takes as long as you like. Every puzzle is saved on its own, so you can go a little at a time. ■ At your own pace, for the long run No timer. Nothing that compares you with friends. Take a break for a while — your progress and everything you've collected stay just as they were. Just one puzzle today is fine. It's a game for working through 2,000 puzzles, little by little, at your own speed. ■ The ghosts, and things to collect Keepy, Mimo, Zuzu, Piri and Tobi. They chatter away beside you while you think. As you go, new wallpaper themes, sound sets and ghost friends join you. Milestones in puzzles solved, diamonds and crowns, your Logic Rating — more than 50 rewards mark the way on a long journey. ■ Ads and money 1,110 puzzles are free — no time limit, no play limit on any of them. There are ads: occasional ones between rounds, and a video when you ask for a hint. You can buy them away. Everything is a one-time purchase. There is no subscription. · EXTREME (690 puzzles) · ULTIMATE (200 puzzles) · Remove ads ■ Also · Plays with no connection (only the ads need one) · Progress backs itself up. Link an Apple or Google account and it follows you to a new phone · Available in 14 languages Bit K.K. (Bit Corp.)