Cell_phone_evaluation VGA1000 Cellphone Eval

User Manual: VGA1000

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Heuristic Evaluation of
Three Cellular Phones
Siemens CF62T
Samsung VGA1000
Motorola T720

ISE 217, Human Computer Interaction
San Jose State University
May 2005
Allison Eckholm
Robert Murphy
Richard Pack

Cell Phone Evaluation

Introduction
This is a heuristic evaluation of three different cellular phones, Siemens CF62T,
Samsung VGA1000 and Motorola T720 (for pictures, see Appendices E and F).
Evaluation concentrated on two distinct aspects of the phones: 1) the initial state or
default state of the phone, covering the software display and the physical keypad layout;
2) the phonebook feature, covering the software display and functionality. Evaluation
was based on a set of nine heuristics and a set of platform standards, established by the
evaluators prior to conducting the evaluation (see Appendix A).
In addition to compliance with stated guidelines and standards, a compliance rating was
conducted, providing comparison values between phones, for each heuristic considered.
Ratings are graphed for each evaluation (initial state, phonebook feature), comparing
each phone per heuristic (see Appendix B), and overall average rating (see Appendix
C).
This evaluation also includes a comparison of the number of steps or key presses for
three specific tasks: 1) completing a new phonebook entry (novice method); 2)
completing a new phonebook entry (expert method); 3) editing an existing phonebook
entry (see Appendix D).

Initial State
1) Feedback and Visibility of System Status
Siemens CF62T - The initial state shows signal strength, battery strength, whether the
phone’s ringer is turned on, date and time, missed calls and messages. The system
visibility is very clear. Rating: 5
Samsung VGA1000 - System status is represented by icons on two displays: one
internal and the other external. A set of icons provide feedback for system status. These
icons include (1) ringer type (2) voice mail (3) signal strength (4) alarm active (5) battery
state/level (6) GPS status and (7) missed calls. Incoming call feedback is available on
both displays. All of these icons are available on both the internal and external screen
save for the GPS status, are easy to see at a glance. Rating: 5
Motorola T720 - Feedback and system status of this display includes signal strength,
ring volume or vibrate state, battery strength, date and time (analog and digital), missed
calls and messages available. All these elements are clearly displayed and easy to read
at a glance. Rating: 5

2) Speak User's Language and Real-World Conventions
Siemens CF62T - This display uses simple icons which are easily recognizable, such as
a picture of a bell crossed out to indicate that the sound is turned off. The battery icon
looks just like a real battery and clearly shows how charged the phone is. The keypad

Cell Phone Evaluation

uses a green phone symbol to indicate the start of a call, and a red phone symbol to
indicate the end of a call. These correspond with the real world convention of green = go
and red = stop. There are only two textual items in the initial state, one is the “Menu”
option, and the second is the “T-zones” option. Menu is a common and well-understood
word, but the phrase “T-zones” does not correspond with any real world knowledge. The
user would have to choose the T-zone option to find out what is meant by that term.
Rating: 4
Samsung VGA1000 - The initial state of the phone has eight textual references split
between the Screens: (1) the time (2) the date and (3) the vibration alert status and the
Buttons (4) ok (5) talk (6) back (7) end and (8) menu. The time is in standard format, the
hour colon separated from the minute followed by the meridian. The vibration alert
message says ‘vibrate’ if active and the date is in the standard format of day of the
week, month, day of the month format. Textual references (1) and (2) are available on
both the internal and external displays, reference (3) is available on only the internal
screen. Rating: 5
Motorola T720 - This initial state has very few textual references, those that do appear
are limited to one or two words, which are clear and easy to understand. Time is
provided in both analog and digital format, for quick, easy, and detailed reference. The
icons on this display are accurate symbols of their real-world counterpart, for example
ring styles are represented by bells, the calendar is represented by a date book with a
digital date displayed. The pick-up button is green, with a phone handle lifted up, the
hang-up button is red, with the phone handle positioned on a phone. Rating: 5

3) User Control and Freedom
Siemens CF62T - The user has the opportunity to press the red hang-up button to either
back out of whatever menu option they have chosen, or to hold the button down to turn
off the phone completely. Rating: 5
Samsung VGA1000 - There is no support for Undo and Redo functions, however at any
time the ‘End’ button if pressed can be used as a “emergency exit” button to return to the
main screen during any task. If the ‘End’ button is held down at any time the phone
powers off. Rating: 5
Motorola T720 - The most common functions of a cell phone are accessible from this
state within one click. These include, ring styles, recent calls, calendar, phonebook,
internet access, and message center. The ring volume is also located via buttons on the
side of the phone. Rating: 5

4) Consistency and Standards
Siemens CF62T - The initial state matches cellular phone conventions because the start
call button is on the left, the hang-up button is on the right, and the numbers on the key
pad follow the traditional ordering of 1 – 0. There is also a directional navigation pad in
the center and a charging port on the bottom of the phone. Other standards that are
followed are the battery strength icon on the right, the signal strength icon on the left, the
time and date and missed call indicators. Rating: 5
2

Cell Phone Evaluation

Samsung VGA1000 - Several adherence to standards can be observed in the initial
state of the VGA1000. It has a standard numerical keypad layout, consisting of buttons 0
through 9, a directional pad, a select button and talk and end buttons. However the
duplication of the OK function to match that of the select button is slightly confusing.
There is a charging plug on the bottom of the phone. Rating: 3.5
Motorola T720 - This phone follows standard telephone conventions for the basic
numeric key layout, but fails to follow cell or cordless phone conventions for the
activation/pick-up and de-activation/hang-up keys. These are clearly indicated by the red
and green icons mentioned above, but are in the reversed position to other electronic
phones: the activation/pick-up key is on the right side, and de-activation/hang-up key is
on the left side. System icons follow standards for reception, battery charge, and
date/time formatting. The layout of the phone'
s main function keys, follows standards in
providing a four point directional or navigation pad. The headphone plug, and the
speaker and microphone are in positions consistent with standard phones. Rating: 4

5) Error Prevention and Error Messages
Siemens CF62T - Not applicable. Rating: 0
Samsung VGA1000 - Not applicable. Rating: 0
Motorola T720 - Not applicable. Rating: 0

6) Recognition rather than Recall
Siemens CF62T - The icons on the initial state make it easy for the user to recognize
what they are looking for. There are not many items displayed on the screen, so
recognition is easy. Rating: 5
Samsung VGA1000 - The presence of common, recognizable and prominent icons on
the screen all aid the user in recognition. Rating: 5
Motorola T720 - Most functions and options at this state are easily recognized.
However, the previously mentioned placement of the pick-up and hang-up buttons
caused errors with early use of the phone, and required recall of position and function to
avoid errors. In addition, one function key, in the top center of the key layout and bottom
center of display, is not easily recognized. The icon consists of a thick horizontal bar,
above three thin horizontal bars, intending to represent a computer menu. This icon is
not easily recognized, and requires recall of functionality, where to find additional
options. Rating: 3

7) Flexibility and Efficiency of Use
Siemens CF62T - Instead of pushing the “Menu” button, more experienced users can
navigate with the direction pad above the numbers on the key pad. Novice users can
simply choose the menu option. Rating: 5
Samsung VGA1000 - For advanced users, the direction pad doubles as a four
programmable shortcut keys eliminating the need to navigate the menu for common

Cell Phone Evaluation

tasks. For novice users, the menu can be navigated to locate the needed feature.
Rating: 5
Motorola T720 - There are no advanced features specific to the initial state of the
phone. As mentioned, the most frequently used functions are available within one click
and shortcut keys for other functions are available from this state. Color and background
images can be set to customize the display in this state. Rating: 5

8) Aesthetic and Minimalist Design
Siemens CF62T - The things that are available on the initial screen without any
navigation are items that are very important when using a cell phone. For example, a
user would not make a call if they saw that they absolutely no signal at that time. There
is no extraneous information in this display. Rating: 5
Samsung VGA1000 - The phone’s screen in the initial state has a minimum of items,
providing the user with the basic information needed, for example they can see if the
battery needs charging or if there is enough signal to place a call. Rating: 5
Motorola T720 - The design is clean and minimal, with clear distinction between
elements. Rating: 5

9) Help and Documentation
Siemens CF62T - No on-line help or documentation is available. Rating: 0
Samsung VGA1000 - No on-line help or documentation is available. Rating: 0
Motorola T720 - No on-line help or documentation is available. Rating: 0

Cell Phone Evaluation

Phonebook Function
1) Feedback and Visibility of System Status
Siemens CF62T - At the top of the “New Entry” screen there is a picture of a pencil and
some numbers, and there is also a picture of an open book. These things clearly indicate
where the user is and why they are here. Rating: 5
Samsung VGA1000 - In the “Add new entry” screen the user isn’t aware of the current
action as the text at the top of the screen only says “Enter Phone #”. Rating: 5
Motorola T720 - When viewing the first phonebook page (one'
s list of saved numbers),
the mode is clearly indicated at the top of the display, with the header "Phonebook." This
header is actually part of the scrolling list of saved phone numbers, so when one scrolls
beyond the displayed list, the header scrolls out of view also, loosing the mode display.
Additional pages within the phone book do not have this issue, and are clearly indicated
with relevant headers. When a change is made to an entry, feedback is provided,
indicating the change has been saved. Rating: 4

2) Speak User's Language and Real-World Conventions
Siemens CF62T - When entering a new phone number the user can chose to put it in
either a VIP group or no group at all. All the text on the screen is written using common
terms that match what people encounter in the real world. Rating: 5
Samsung VGA1000 - While adding a new entry into the phone book the dialogs speak
the users language with feedback messages and dialog titles. The user is able to group
numbers together, select type of number, ie cell phone and add other information about
the entry. Rating: 5
Motorola T720 - All options and references are in textual format using common terms
and language, no icons are used requiring interpretations. The concept of a physical
phonebook is maintained through this electronic medium, following normal conventions,
storing names and numbers, listed alphabetically. Rating: 5

3) User Control and Freedom
Siemens CF62T - There are several features that let the user undo or cancel the
process of entering a new phone number. One way is to press the button corresponding
to “cancel” on the screen, and another is to press the red hang-up button which is
always present on the keypad. Once a character has been typed a “clear” option
appears on the left, which allows the user to delete the last character entered. There is
no redo feature. Rating: 4
Samsung VGA1000 - Like the initial state there is the same support for the emergency
exit “End” button. A back button is provided on each of the screens but no undo/redo
action was provided. Rating: 5

Cell Phone Evaluation

Motorola T720 - Several functions are available for storing, editing and sorting phone
numbers. At any point, one may exit or abandon their process by using the hang-up key,
which returns the user to the initial state. Although, after one steps through and simply
views the options within the "edit" mode, when returning to the previous pages they will
encounter a display indicating "saved changes," even though no changes were made on
the entry. Rating: 4

4) Consistency and Standards
Siemens CF62T - The phonebook entry display is consistent with the design of the rest
of the phone’s displays. The cancel button is on the right side of the keypad just above
the hang-up button so it is very easy to remember how to cancel an action. Both of these
buttons are on the right side, which is a standard most cellular phones follow. Rating: 5
Samsung VGA1000 - The layout of the top of the screen is consistent with the Initial
State. The back button selection is on the left of the screen similar to the majority of
cellular phones. Rating: 5
Motorola T720 - The phonebook function follows consistent placement of options, and
follows platform conventions. All selection options, such as "view," "edit" and "change"
are on the bottom right of the display (top right of keypad), and all finished options, such
as "exit," "back" and "done" are on the bottom left of the display (top left of keypad).
Rating: 5

5) Error Prevention and Error Messages
Siemens CF62T - Errors occur very easily while entering letters in the name field.
Characters must be scrolled to very quickly in order to make a choice before the phone
defaults to one. These types of errors could be prevented if a different letter choice
system was used. Rating: 3
Samsung VGA1000 - Errors can occur when entering the name. A back button is
provided which backspaces the last character entered, to help prevent these type of
errors another text entry mode can be chosen called predictive text. Rating: 4
Motorola T720 - The only errors encountered within this function were during text
entering or editing. These errors were easily overcome by a visible and easy to use
"delete" key. No error messages were encountered. Rating: 5

6) Recognition rather than Recall
Siemens CF62T - There is no recall required in this screen of the phonebook. All the
options are textual and easy to see. Rating: 5
Samsung VGA1000 - Each of the items on this page were easy to identify. Rating: 5
Motorola T720 - All options and functions are clearly indicated with relevant textual
reference, all easy to recognize. No icon representation is used, requiring recall of
function, other than previously mentioned menu list. Rating: 5

Cell Phone Evaluation

7) Flexibility and Efficiency of Use
Siemens CF62T - There is a shortcut to the “New Entry” screen that experienced users
might find faster. However, using the center navigation key saves only two button
pushes. The novice users should be able to use the system efficiently regardless of what
method they use to enter the number. Rating: 4
Samsung VGA1000 - There are shortcuts provided to the function “add new entry” that
advanced users might exploit. Novice users might choose to use the menu. Experienced
users will save 4 clicks over novice users. Rating: 4
Motorola T720 - Clearly indicated options allow for ease of use. Alternative methods for
saving phone numbers are available; for example, instead of following several steps to
create a "new entry," a simple "store" option is available, to store a phone number, after
it has been entered. Rating: 5

8) Aesthetic and Minimalist Design
Siemens CF62T - The design contains no unneeded elements yet still provides all the
necessary information. Rating: 5
Samsung VGA1000 - There is no unneeded information on this screen. Rating: 5
Motorola T720 - The design is clean and minimal, with clear distinction between
elements. Rating: 5

Cell Phone Evaluation

Conclusion
Initial State - In the initial state the Siemens CF62T, Samsung VGA1000, and Motorola
T702 phones received identical ratings in 6 out of the 9 heuristics. The ninth heuristic,
help and documentation, was not evaluated because no help or documentation was
available on any of the phones. There was a slight difference for the match between the
system and real world heuristic between the three phones. The Siemens phone did not
speak the users’ language as well as the other two phones. Another heuristic that varied
among the phones was consistency and standards. The Samsung and Motorola phones
both showed some deviation from our set of standards. The last heuristic where
differences could be seen was recognition vs. recall. The Motorola phone received a
rating of 3 compared to 5 for both of the other phones.
Phone Book The three phones received identical ratings for 5 out of the 9 heuristics
after evaluating each phone book. Slight differences were present for visibility of system
status, user control and freedom, and flexibility and efficiency of use. None of the
phones received the highest score on all three of these heuristics. There were larger
differences present for heuristic five, error prevention. The scores ranged from 3 to 5,
with only one phone receiving the highest score.
Clicks per Task - For advanced users there were significant differences in the number
of clicks required to create a new entry in the phone book. The range went from 4 clicks
for the Siemens phone all the way to twelve for the Samsung phone. The range for
novice users was fairly large as well, going from 3 clicks up to 8. Editing an existing entry
showed no differences between the phones, all required 9 clicks to accomplish the task.
Clearly there is room for the Samsung phone to improve its phone book process for the
advanced user. The editing task could probably also be simplified for both the Siemens
and Samsung phones based on the results from the Motorola phone.
Average Rating - There was very little difference in the average ratings for the three
phones. The Siemens and Motorola phones had the same average of 3.89 while the
Samsung was slightly higher at 3.99, with 5 being the highest possible score. The
average scores from the heuristic evaluation reveal that all three phones have decent
user interfaces, but still have room to improve.
Trends - There was only one heuristic that revealed a consistent weakness across both
interfaces, and it was only for one phone. All the phones received a score of 0 on
heuristic 5 for the initial state interface, but the Siemens phone also received a poor
rating for the phone book interface. The consistent bad ratings reveal a design that is
not conducive to error prevention.
With the exception of heuristic 9, help users diagnose and recover from errors, there
were no other heuristics where a phone received bad ratings across the board.

Cell Phone Evaluation

Appendix A
Heuristics and Standards
Heuristics
1) Feedback and System Status
2) Speak User'
s Language and Real-World Conventions
3) User Control and Freedom
4) Consistency and Standards
5) Error Prevention and Error Messages
6) Recognition rather than Recall
7) Flexibility and Efficiency of Use
8) Aesthetic and Minimalist Design
9) Help and Documentation
(From: J. Nielson’s Usability Engineering)
Standards
1) Number / keypad layout (standard telephone layout):
1st (top) row: 1 2 3
2nd row: 4 5 6
3rd row: 7 8 9
4th row: * 0 #
2) Send-call & Hang-up keys:
Send-call Key: Top left of keypad
Hang-up key: Top right of keypad
3) Reception signal indicator:
Set of incrementally taller vertical bars
4) Battery charge state indicator:
Image of traditional battery (ex: AA, C, D battery shape), incrementally filled in,
indicated level of remaining charge.
5) Direction / Navigation pad:
4 point directional buttons or keypad (top, right, bottom, left) for navigation
through icons or menus.
7) Speaker and microphone location:
Positioned for most efficient use, most proximate location to ear and mouth when
held for conversational use.
6) Headphone plug
Available

Cell Phone Evaluation

Appendix B

Cell Phone Evaluation

Appendix C

Cell Phone Evaluation

Appendix D

Task 1: Completing a new phonebook entry (novice/long method)
Siemens CF62T: 6
Samsung VGA1000: 12
Motorola T720: 8
Task 2: Completing a new phonebook entry (expert/short method)
Siemens CF62T: 4
Samsung VGA1000: 8
Motorola T720: 3
Task 3: Editing an existing phonebook entry
Siemens CF62T: 9
Samsung VGA1000: 9
Motorola T720: 9

Cell Phone Evaluation

Appendix E
Samsung VGA1000

Cell Phone Evaluation

Appendix F
Motorola T720

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