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 app randomly generates a huge number of possible puzzles without any predefined patterns. The app usually sets 4 to 6 numbers for each puzzle, and the player needs to finish the rest. The solution must be unique for each game. Tap a square and a list of 5 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. Tap the "Check" button to check the correctness of the result. Tap the "New" button to start a new puzzle. Tap the "Undo" button to reverse the previous actions. Tap "Redo" button to restore those actions reversed by "Undo". Tap "Help" button to get instructions. Although 5x5 size reduces complexity of 9x9 sudoku, the irregular (or pentomino) regions of puzzles introduces challenges not seen in regular sudoku. Logi5Puzz is very good for those who do not want to spend long time playing regular 9x9 sudoku, and young kids to whom 9x9 sudoku is too challenging. It helps kids develop problem solving skills. Kids 4-6 years old may start to play. It is great fun for adults to play and keep their brain sharp. Please also check out Logi5Puzz+, an advanced version with more features: 1. Grid sizes configurable from 3x3 to 16x16 on iPad, and from 3x3 to 9x9 on iPhone. 2. Absolutely advertisement free. No internet connection required to play. 3. Optional smart/manual notes (pencil mark), hints and passcode lock. 4. Plays two games simultaneously and switch any time.