Reviewed
by: Howard
Carson, March 2007
Published
by: Deluxeware & Island
Labs
Requires: Palm
OS 5 1.1MB free memory
MSRP: US$12.95
Normally we don't review inexpensive Palm OS, smartphone
or Windows Mobile/Pocket PC games, but Sudoku is a craze
that's no longer the original little fan game it was
after Dell Magazines first introduced its version in
the 1970's. In fact, Sudoku (after expriencing wild growth
in popularity since 2001) seems to have settled into
a well deserved place in the pantheon of programs that
are must-haves for every Palm OS, smartphone or Windows
Mobile/Pocket PC. The best of breed for Palm OS right
now seems to be Numberz, made by Jampaq Software. Contenders
for the Palm OS Sudoku crown have got to beat Numberz
before they can reach for the top. Zen Sudoku has stepped
up.
According
to Wikipedia's excellent article on the subject,
Sudoku puzzles are actually a special case of Latin
Squares—any solution to a Sudoku puzzle
is in fact a Latin square. Sudoku imposes the additional
restriction that 3×3 subgroups must also contain
the digits 1–9 (in the standard version). This
particular type of puzzle as we know it was first published
in the late 1970’s in Math Puzzles and Logic
Problems magazine by Dell Magazines. The name given
by Dell to these puzzles was Number Place, as they
are still called by this company until today. Dell
took Euler’s Latin Square concept and applied
it to a 9x9 grid with the addition of nine 3x3 sub-grids,
or boxes, each containing all numbers from 1 to 9.
So the Sudoku concept was not invented in Japan as
many people may believe, but the name Sudoku was. In
1984, Nikoli, Japan’s leading puzzle creating
company, discovered Dell’s Number Place and decided
to present it to Japanese puzzle fans. The puzzles,
which were first named Suuji Wa Dokushin Ni Kagiru,
("the numbers must be single" or "the
numbers must occur only once") quickly became
popular. In 1986, after some important improvements
were added mainly by making symmetrical patterns
and reducing the number of given clues, Sudoku became
one of the best selling puzzles in Japan. Realizing
that the only problem with the Sudoku puzzles was
their long name, Kaji Maki, the president of Nikoli
abbreviated it to Sudoku: Su = number, digit; Doku
= single, unmarried. Today there are more than 600,000
copies of Sudoku magazines published solely in Japan
every month. |
Zen Sudoku (and Sudoku in all its guises) is a deceptively
simply game. It takes place on a board divided into a grid
of 81 squares divided into 9 sets of 9 squares (3x3 subgroups).
The goal is to place one instance of the numbers 1 through
in each column and row, with all of the numbers 1 through
9 also appearing in each of the 9 sets of 9 squares. Each
game begins with some numbers already placed strategically
on the board to help you get started. Easy levels provide
a lot of starting numbers. As you progress to more difficult
levels, there are fewer and fewer starting numbers provided.
As well in the more difficult levels, the few starting numbers
are placed in positions which offer little or no hint for
other number positions.
At all levels of game play, you'll find that there seem to be several
possible numbers that can be placed in most of the empty squares. The
thing is, there's actually only one correct solution for each board.
Zen Sudoku, like most of its competitors, offers a feature called Pencil
Marks which essentially allows you to mark down the possibilities for
each empty square, gradually eliminating the possibilities as you find
more and more correct numbers. But because there are often several incorrect
possibilities for each of the empty squares, it's also possible to play
to a point where you can't make any more moves and end up with unsolved
empty squares. That means you have to backtrack. Zen Sudoku (all good
Sudoku) is challenging and provides terrific exercise for your brain.
Cons: Zen Sudoku has all the right things going for it,
but is unfortunately cursed with a visually distracting game
board. The separation grid lines between the nine-squares
are drawn using a low contrast color and we found ourselves
constantly checking to ensure that we were actually estimating
number positions for the correct set of squares. So why didn't
we simply turn off the distracting background graphics? Because
the configuration settings do not allow it. Unlike Numberz,
there's no move checker to determine after a particular move
if the game is still solvable. Purists might recoil at this
(and some purists I know who play Numberz never use the move
checker), but I personally don't find that the feature detracts
from game play. Discipline and patience, when playing Sudoku,
are everything. I think that it's a comparatively small effort
for Deluxeware or Island Labs to tweak the Zen Sudoku game
code and configuration screen so that graphic backgrounds
can be turned off, add more visual contrast to the nine-square
grid, and add a move checker button.
Pros: One
of the Sudoku fanatics I know has color acuity issues and,
unexpectedly, that deficiency allowed him to see the Zen
Sudoku nine-square sections quite clearly. He wondered
out loud what all the fuss was about. He loves Zen Sudoku
and we certainly understand why. We just wish we could
play it as enjoyably too, because the game has all the
right functionality. Zen Sudoku responds quickly to taps
and drags, and the number grid pop-up is a clever alternative
to dragging & dropping
a selected number to a square. Just tap & hold a blank
square in any part of the grid and a little sub-grid pops
up containing only available number choices—tap your
selection. The game level and puzzle logic seems to be different
than Numberz, so if you're already used to Numberz you may
find that it takes significantly longer—as long as
several weeks, or even a couple of months—to work your
way up to the Very Hard level in Zen Sudoku. All in all it's
a worthy addition to the Sudoku lineup. Download the trial
version to give it a try.
