Sudoku Master Premium: Offline

What this offline sudoku game is for

Maybe you have ten minutes on a train, or you want a puzzle to clear your head before work. This is a classic 9x9 sudoku game built for that kind of sitting down and solving, with no network connection needed to play.

The developer lists more than 5000 puzzles, and says each one has only a single solution. The listing also suggests one or two puzzles as a morning warm-up, which is the most specific use it describes.

It is pitched at both first-time solvers and people who have moved on to harder grids, so the difficulty range does most of the work of fitting it to you.

Choosing a difficulty and working a grid

Puzzles come in four levels: easy, medium, hard and expert. You pick whichever level suits the time you have or the skill you want to test.

When you select a cell, the row, column and box around it are highlighted, which helps you check which numbers are still possible. Notes mode can be switched on or off, so you can pencil in candidate numbers only when you want them.

Highlight Duplicates flags numbers that repeat within a row, column or block. A separate toggle highlights identical numbers across the grid. Both can be turned off if you prefer to spot clashes yourself.

Hints, undo and the eraser

Hints are described as free and unlimited, and they guide you through the numbers when you are stuck. The developer also mentions an auto-check feature alongside them.

Undo and redo are both unlimited, so a wrong move can be reversed without losing the rest of the grid. The eraser removes mistakes you have already entered.

Together these tools mean a mistake costs a few taps to fix rather than a restart. Each one is listed as part of the free feature set.

Saving progress and playing in the dark

Auto-save keeps a game with numbers still missing. Close the app and it resumes from where you left off, with no time limit to worry about.

Three colour themes are offered, which the developer says make the screen easier on the eyes, including in the dark. Sound effects are included as well, and they can be part of the feel of a session.

Because nothing in the description needs a connection, the same grids and saved games are available whenever you open it, on a train or anywhere else without signal.

Tracking times across each difficulty

Statistics are kept separately for each difficulty level. They record your best time on each level and the achievements you earn.

If you want to see whether expert puzzles are getting quicker over time, the per-difficulty split is what gives you that comparison.