for the Palm OS and Pocket PC
Posted April 2004 by By Tanker Bob
Text messaging over your cell phone can
be an exercise in frustration. Even with T9, messaging requires
patience and endurance. Some simply accept the inconvenience.
Others look for a better way. Dr. Saied Nesbat took his PhD
in Electrical Engineering and rose to the challenge, starting ExIdeas,
Inc. Dr. Nesbat researched the literature, taught himself
user interface design, and created a complete and useful
text input system using just the 12 keys on a cell phone.
After completing that project for hard key devices, he applied
that the same input system to “soft key” environments
and birthed MessagEase for
Palm OS, Pocket PC and tablet PCs.
As one would expect from a PhD in EE, Dr.
Nesbat based the design for MessagEase on sound analytical
principles. He used Fitts'
Law, the concept that the time to acquire a target is
a function of the distance to and size of the target put
into mathematical terms, as a starting point. He combined
this with M. S. Mayzner and N.E. Tresselt's tables of single-letter
and digram (2-letter combinations) frequencies for various
word-length and letter-position combinations in their 1965 Psychonomic
Monograph Supplement s. Dr. Nesbat used his background
in design-for-test to mathematically optimize the letter
placement based on all these factors. After considerable
optimization, the resultant compact MessagEase (ME) took
text input systems to a new high. You can read his original
paper in PDF format here.
The overall keyboard design actually uses
two primary keypads. As you can see from the illustration,
ME uses just nine keys to enter the entire 26-character English
alphabet. The nine most common letters— E, T, A, O,
N, I, S, and H—account for about 71% of the English
usage and appear on the nine main keys. Just tap them to
get them. For the most part, the next eight most common letters
appear around the center ‘O'. The user accesses these
by putting the stylus down anywhere in the ‘O' key
and sliding in the appropriate direction. Except for the
least common letter ‘Z', the rest appear such that
a stroke towards center from the outside keys brings them
up. I said for the most part because the math showed little
speed gain for some of the secondary letter placements. Dr.
Nesbat decided to place the rounded secondary characters
around the ‘O' and the angular letters on the outside
for ease of learning, carefully located to produce no real
loss of performance. Thus, the entire alphabet can be accessed
by either a tap or tap-and-slide with just nine keys. This
all resulted in an extremely fast “keyboard” that's
relatively quick to learn.
The numbers and punctuation appear on the
other side of the input area. The spacebar, which is the “letter” of
the most frequency occurrence in writing (18.7% vs. ‘E'
at 13.3% when space is considered a 27th “letter”),
occupies a large part of the middle ground for speedy targeting.
Although the punctuation appears on the number pad, it also
comes up from the letter pad from the points not occupied
by letters. For example, stroking left on the number 3 produces
a ‘?', and down on ‘E' a period. All the common
punctuation may be accessed in this way. This includes common
digrams involving the space bar. Period, colon, semi-colon,
and comma all drag down towards the space bar which almost
always succeeds them in normal writing. All this minimizes
hand movements during normal text entry to almost nothing.
MessagEase also easily handles special
characters. Accented, etc., letters can be done in several
ways. The user can enter a letter and its accent in succession,
then stroke up to the NNW direction on the ‘A' key
to combine the letter and accent into a single accented letter.
Sliding back and forth on some letter keys also produces
a special character, and the manual lists all those. Lastly,
the keys can be reprogrammed (see below), and you can add
your most-used special characters to the keyboard itself.
At the center of the keyboard are two special
keys. The top-center key puts all the common Palm functions
just a stroke away. These include copy, cut, paste, undo,
shortcut, and the command stroke, as well as moving to the
next or previous database field. The “Star” key
below it can be programmed by the user, which we'll discuss
I tested MessagEase (ME) on my Palm Tungsten|T3.
This version, MessagEase4T3 (ME4T3) 1.7, installs as a replacement
for the middle Graffiti 2 input skin (the one with three
input panels) on the Palm's Dynamic Input Area (DIA). ME
or Graffiti 2 can be selected by tapping on their keys on
either side of the keyboard itself, and the core Palm functions
like Home and Menu are likewise present. The skin colors
match the T3's stock status bar nicely. ME4T3 works in portrait
and landscape on the T3, which at this writing is unique
amongst non-QWERTY keyboards. The layout of the panel suits
it well for varying screen orientations.
Upon installation and execution of the
control program, you select which keyboard layout that you
prefer. The installation of new keyboards couldn't be simpler.
The choices include letters on the left or right, and on
the stamps for other PDAs, a special keyboard with just the
letters and numbers for experienced users. The T3 DIA implementation
doesn't require calibration, but the stamps for other units
may require it to ensure accurate input.
Setup options provide what you'd expect.
Drag length to obtain characters can be set as desired. Circling
on the main letters can either produce numbers clockwise
or counter-clockwise, or you can have ME capitalize the letter
circled upon. You can set the up/down arrows on the system
key to change pages, selection, or fields. The next option
either protects the letter/number keys as preprogrammed or
allows you to reprogram them with special characters for
another language. The checkboxes can set auto capitalization,
key clicking, or fix problems in the last two pixel rows
of some handhelds.
Perhaps the greatest strength of the MessagEase
system comes from its macro support. ME supports 32 special
macro commands, all of which can be applied to various parts
of the keyboard. It can also store/recall text strings as
well. Words can't begin to capture the power of this capability.
The Star key is reserved for users to program with these
macros for easy access. Key assignments and macros can be
viewed using the ‘?' key at the bottom of the keyboard.
I listed my Star key macros in the illustration. They include
changing word capitalization to all upper, all lower, sentence
case, and title case, and select text to beginning and end
of the line. The manual lists the special macros in addition
to the entire ASCII code compendium for those that want to
customize their keyboard.
What factors make MessagEase unique amongst
alternate keyboard offerings? First, its compactness, packing
the alphabet into just a few keys. This keeps hand movement
to an absolute minimum while making it useful on smart cards
as well. It also allows the individual keys to be larger
than normal keyboard layouts, improving accuracy and speed.
Second, because of its roots in Fitts' Law, it can be scaled
in size within reason. Thus it works just as well on PDAs
and tablet PCs, and perhaps applications not yet considered.
Third, ME is platform independent. The core letter keypad
is basically a 3 x 4 pattern, which cell phones, security
keypads, calculators, and other devices use. The possibilities
are almost endless.
So, how does it work? Marvelously! I'm
no speed demon at text input of any kind. My Graffiti input
maxed out around 12 words per minute or so on a great day,
not even counting all my errors. I could never take notes
in a meeting with Graffiti 1 or 2. I've been able to do just
over 25 WPM with other soft keyboards—nothing to sneeze
at but still not note taking speed. MessagEase brought my
input up to over 35 WPM, which is really flying for me. Writing
normal text requires almost an infinitesimal amount of hand
movement. This is borne out by a paper done by Shumin Zhai,
Michael Hunter, and Barton Smith available in PDF format here,
which compares a variety of keyboard layouts using Fitts'
Law. Dr. Nesbat used their methodology to test MessagEase
under identical conditions, and recorded the results in his
paper cited earlier. Their scientific results match my own
experience. I use the text-editing macros every day. Like
any input method, ME has an associated learning curve. Dr.
Nesbat minimized this by his clever placement of the letter
sets, but it still takes a bit of practice to become proficient.
MessagEase proved a joy to use, looked
great, and increased my text input speed by 41%. The well-thought-out
compact keypad, powerful macro capability, ready access
to numbers and a wide variety of punctuation/symbols, and
landscape support for the T3 set MessagEase apart from
its competition. MessagEase can also be had as a stand-alone
program and MessagEaseKB, a replacement for the built-in
Palm soft keyboard. The latter can be particularly handy
if you own a Palm Tungsten T model and want to write without
opening your slider. Other versions of ME support other
Palm OS PDAs, Pocket PC handhelds and Tablet PCs. Available
as shareware for just $22.50, ME4T3 has
returned as my primary, indeed only, input method for my