Logi5Puzz+ 3x3 to 16x16 Sudoku [iPhone]

Based on highly rated Logi5Puzz, Logi5Puzz+ is an advanced version with more features:
1. Grid sizes configurable from 3x3 to 16x16 for all supported devices.
2. Absolutely advertisement free. Never use internet connection.
3. Optional smart/manual notes (pencil mark), hints and passcode lock.
4. Plays two games simultaneously and switch any time.
5. Supports macOS.

Logi-5 Puzzle is a variation of Sudoku game. A 5x5 grid of squares is divided into 5 irregular (or pentomino) regions, each with 5 squares of the same color. The objective is to fill the grid so that each row, each column, and each region contains all of the 5 digits from 1 to 5. In other words, each digit should appear exactly once in each row, each column, and each region.

Logi5Puzz+ extends the grid sizes from 3x3 to 16x16, with or without regular option. A 9x9 regular choice with 3x3 square block for each region is the same as the common Sudoku game. A 4x4 regular grid has 2x2 square block for each region, a 6x6 regular grid has 2x3 rectangle block for each region, a 16x16 grid has 4x4 square block for each region, and so on. The shape of each region is random for irregular grids (or jigsaw sudoku) of all sizes.

Logi5Puzz+ app randomly generates a huge number of possible puzzles without any predefined patterns for each grid size. The app presets a few numbers for each puzzle, and the player needs to finish the rest. The solution must be unique for each game. Because the app creates puzzles on the fly without using a big database to store pre-generated puzzles, it can combine so many sizes within one app, produces virtually unlimited numbers of puzzles, and utilize a very small storage space at the same time.

Logi5Puzz+ provides good value:

1. Logi5Puzz+ plays common Sudoku games too, and a single purchase delivers Sudoku, Logi-5 puzzles, and much more choices.
2. It serves both beginners (with 3x3 grid size) and expert players (with 9x9 irregular or 10x10 to 16x16).
3. Universal purchase enables a single purchase to work for Mac, iPad, iPhone and iPod touch devices.
4. All features and unlimited puzzles included. No in-app purchase to buy additional games, or levels.
5. It allows family sharing.

The app can be an education tool for a beginner or young kid to learn Sudoku, by starting with 3x3 sizes, and then gradually increasing grid sizes. The irregular regions of puzzles introduces fun not seen in regular Sudoku, and those who have been good at regular Sudoku can try 9x9 irregular (nonomino sudoku). Very advanced Sudoku players can play 10x10 up to 16x16 sizes.

The app can be configured to provide optional hints. A passcode can be set to lock the options on the maximum number of hints allowed, or whether restarting the game before finish is permitted. For example, a parent can lock the options with a passcode to ensure that a child honestly finishes a puzzle without any hint or restarting.

Tap a square and a list of digits plus a blank button will pop up for the player to choose a number to fill into that square. Select the blank button to clear the existing number in the square. When notes (pencil mark) are enabled by "Setup", tiny notation digits inside each empty square are entered automatically (with smart option) or edited manually by selecting the notes button.

Tap the "New" button to start a new puzzle. Tap the "Check" button to check the correctness of the result. Tap the "Undo" button to reverse the previous actions. Tap "Redo" button to restore those actions reversed by "Undo". Tap "Setup" button to configure various settings. Tap "Swap" button to play two games simultaneously and switch between them. Two games have independent setups to choose different sizes. Tap "Help" button to get instructions. Tap "Hint" button to get a hint, if you have used "Setup" button to allow a hint.

When digits become illegible for a large-size puzzle on a small-screen iPhone or reading notes, you can zoom the grid with two-finger pinches and pan.