The game has space for 3 profiles if you want to let anyone else use your DSi.
The art style for this game has a background of strune Sudoku boards scrolling to the right with transparent options on top. This could be an annoying distraction because the Sudoku puzzle boards are not solid white & black but are transparent. It automatically saves a game you exit for each of the 5 game types.
It has an Auto Correction that can be turn off before each puzzle board is selected. Off, you will not receive a +1 minute penalty for entering the wrong number but in it will not then tell you if you have the correct number, I see no mark in your stats if you use it. You can buy a Hint for a +1 minute penalty.
There are 4 types of Sudoku to choose from, each has 4 difficulty levels labeled the same for Kakuro, 2 are open at the start. Sudoku has 180 puzzles, Sudoku X has 80 puzzles, Jigsaw Sudoku has 80 puzzles, and Mini Sudoku has 80 puzzles.
Sudoku X plays like regular Sudoku except that the opposite corners that are connected diagonally and can only have numbers 1-9, the middle space is shared.
Jigsaw Sudoku does have 9 spaces that have to be filled 1-9 but the areas are no longer 3-3 squares but random shapes for each puzzle. The outline for the shapes are a thin red lines, not as defined as the black.
Mini Sudoku has 3-2 rectangles that are filled with numbers 1-6, fun for quick little sessions.
The Kakuro plays like a crossword game with numbers, where it has a maximum number in an arrow that points to a column or row with spaces that when filled must have numbers that equal the maximum number, unlike the Sudoku it's played on a solid black & white board. Like the other for game types, Kakuro has 4 difficulty levels, Gentle with 15 boards, Moderate with 25 boards, Tough with 25 boards, and Diabolical with 15 boards. Gentle and Moderate are accessible from the start.
The Options let you choose 4 simple tunes, or to turn them off and just listen to the sound effects if you want, though the sound effect for the scroll-bar limit was a poor choice and can be annoying.
The Status has 6 pages where you can see your profile progress summary or individual stats for Sudoku, Sudoku X, Jigsaw Sudoku, Mini Sudoku, and Kakuro. The Summary shows your "Global" Progress: #/500 which is the number of puzzle available and number you have beaten. A "Global" Ranking: #, which is the number of stars you have achieved from your games, 5 maximum stars per game based on time to complete each game, 1 mistake equals 1 minute added to your time. The Summary also shows Total Played Time, Best Time, Average Time, and Average rank.
And that's all I see. I wrote a review for you, feel free to write one on any DSiWare games that you have, it doesn't have to be good obviously. I couldn't find anything to help me decide on which Sudoku game to get but luckily I found a suitable one.