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PDA Usability

A Workshop on

“Designing for Handheld Usability”Scott Weiss

(Usable Products Co.)

at the 46th Annual Meeting of the Human Factors and Ergonomics Society,Baltimore,MD

~ Presented to IE 445/545 by ~Anand Moulik

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Presentation Outline

• Handheld vs. Desktop

• Prototyping

• Usability Testing

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Handheld vs. Desktop

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Desktop Definition

Essential Components: CPU (Central Processing Unit), the

“brain” Display Keyboard Pointing device, typically a mouse Cables to connect the components to

each other, to power, and to a network

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Handheld DefinitionHandheld devices are extremely portable, self-contained information management and communication devices.

They must be able to:1. Operate without cables, except temporarily

(recharging, synchronizing with a desktop).2. Be easily used while in one’s hands (no

furniture necessary!).3. Support the addition of additional applications

or support Internet connectivity (WAP, i-mode, or email).

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WAP

Wireless Application Protocol: not a language, operating system, etc.

Term is used generically, however. Available on most available mobile telephone

handsets. Latest Openwave browser supports color

graphics, graphical user interface controls, and limited filing capabilities.

Not SMS. SMS is a messaging standard that appears on all WAP devices.

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i-mode

Extremely popular service in Japan that is coming to Europe and North America.

Uses C-HTML (Compact HTML), which is similar to HTML.

Supports Internet POP3 email from the handset. The NTT DoCoMo network already supports

packet switched data.

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Pocket PC Miniature version of desktop Windows. Supports a file system. Has a multitasking operating system. Increasing market share in the PDA arena.

                                                                                                

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OS

Currently the most popular PDA operating system. Available also on Kyocera 6035, Samsung i300,

Handspring VisorPhone and Treo.

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OS Found in a wide variety of devices, including the

Ericsson R380 and Nokia 9210 communicators. Also found in Psion palmtop computers. Symbian UI is hidden behind proprietary

operating environments. Some devices even hide the API (application-

programmer interface), such as the Ericsson R380—its API is WAP.

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RIM OS Found on RIM Wireless Handheld™ pagers, such

as the RIM 857 and RIM 957. Simple graphical design, mostly text and icons. Input restricted to keyboard and roller wheel. User interfaces mostly vertically-oriented forms.

                      

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Wisdom™ OS Found on the Accompli™ 009 communicator and

Timeport™ P935 pager. Rich, graphical user interface that requires a

keyboard.

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Hardware: Desktop vs PDA

Form Factor: device centric vs. task centric Mobility: usually tethered vs. usually wireless Connectivity:

continuous & stable vs. punctuated & volatile Input: standardized vs. varied & evolving Display: large vs. small Memory: powerful vs. limited Storage: vast vs. limited Interaction: metaphors, boot times, file

systems vary

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Handheld Usability?Is designing for handheld any different?

Yes & No

Methods and context of information access differ; Wide variation in user interfaces; and… Goals and needs of users are shifted.

Attention to detail and better understanding of users is required.

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Conclusion: Handheld vs. Desktop

Each platform and each device has own set of user interface controls and interaction methods.

Design needs to be rethought for each implementation.

Guides for specific devices and platforms are available.

More important to think from the user’s perspective than to attempt to port directly from the desktop.

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Conclusion: Handheld vs. Desktop

Different design strategy is required. Mobility, limited memory & processing power,

small display sizes: challenges & opportunities.

Handhelds are heavily reliant on desktops. Future: less reliant, but more interaction

between devices and device types.

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Prototyping

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Paper Prototypes

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Paper Prototypes

Primary value is for usability testing. Identify scenarios first. Model the hardware and the software. Paper prototypes are:

– Team oriented– Quicker to correct & change

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Supplies• Large format folders (to store prototypes)

• Black pens

• Transparency markers—permanent

• Transparency markers—wet erase

• Restickable glue stick

• Permanent glue stick

• Transparent tape

• Post-it® correction tape in three sizes

• White card (60# or greater weight)

• Write-on transparencies Colored markers (for color user interfaces)

• Manila folders (to organize user interfaces)

• Q-Tips (to erase wet-erase markers)

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Building Your Model

Model the hardware first. Make it larger than actual, since hands cannot

write as small as LCDs render text. Cut out where the display is located.

Pages go behind. The cutout must match the size of the pages.

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Blinders & Pages

display cutout

softkey labels

softkeys

directional control

WAP Phone Binder WAP Page

Bookmarked Cities1 Add Bookmark2 Montreal 30 Sunny3 Miami, FL 84 Partly Cloudy4 Denver, CO 24 Snow5 New York NY 82 Rain6 Honolulu HI 74 Sunny7 Paris 64 Rain8 London 72 Partly Cloudy9 Delete Bookmark

6.0”6.0”

4.5”4.0”

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Application Pages

display

scroll region

soft keys

horizantaloverflow

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Example Draw the page outline on a sheet of card. Use clear plastic for entry fields.

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Components

Label the back of each UI element with:– Date– Description

Create individual elements for popup menus.

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Specific UI Elements

Buttons Hyperlinks Text entry fields Lists Softkeys Hardware buttons & indicator lights

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Interface Storage

Store sections of the interface on “palettes.” Organize user elements and palettes by use

case. Store palettes in manila folders.

Organization is essential to page generation during testing.

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During Interviews Two respondents One moderator One or two “computers”

observers

moderator respondents “computer”

prototype

“palettes”

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Text Entry

Allow for simplified data entry.– Voice– Explicitly state what they intend to enter.– Input methods vary

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Cursor Movements

Allow respondents to use tabbed extenders on the pages to emulate the scrolling affordances on the device.

Clicks may be made verbally on prototype touch screens.

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UI Elements

Must be modeled in its before and after states.

Menus may consist of item strips where dynamic or contextual menus are required.

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Page Changes (Links)

Wait cursors should be displayed for page transitions.

Where ever possible, construct as much of the page beforehand to reduce response time.

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After The Interviews

Create a narrated prototype video to document the prototype.

Model action after user scenarios. Stop action for page and UI transitions. Narration provide description of users

interactions.

Creation of video cements design decisions and proposed interaction quickly.

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Online Prototypes

Ideal for hands off-clients:– Make great executive presentations– Ideal for feedback from focus groups

“Comps” (graphic representations of final products) will not provide usability data, just reactions.

Clickable demos & functional online prototypes:– Provide more realistic setting– Take more time to produce and modify– Moderator must provide the illusion of interactivity

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How to Deploy

Desktop emulators are far from user experience of handheld device.

When possible, demo on the handheld device itself

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Emulators

Available for practically every platform.

Suited for testing code, & demonstrating interfaces, but there are always differences in appearance and behavior.

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Emulators

Advantages Readily available Quicker to develop/

deploy Can be easily video

recorded

Disadvantages Looks and feels like a

desktop computer Input methods

unrealistic Appearance different

from actual device

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Clickable Demos

When moderating, always present the demo as a prototype.

Crashes, lag time, & other bugs will crop up.

When moderating, explain beforehand that you’re working with an early prototype.

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Usability Testing

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What is Usability Testing?

Interviewing people—usually one-on-one—as they attempt to use your product.

Participants, called respondents are recruited from a Respondent Screener.

The Respondent Screener is a questionnaire used to recruit interviews.

Tasks are written in a Discussion Guide. The moderator conducts the interviews,

observing respondents as they succeed and fail. 6 interviews is a typical number.

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Qualitative?

User testing is qualitative. Quantitative testing requires dozens of

respondents—not generally practical. Log files are effective for quantitative analysis. Focus groups are opinion-oriented research with

groups of people. Usability tests are one-on-one.

or Quantitative?

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Usability Process

Facility selection Respondent screener Recruit respondents Discussion guide Conduct interviews Debrief Findings documentation Video highlights Prioritize issues

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Timeline

week 1 week 2 week 3 week 4

discussion guide

conduct interviews

top-line notes

define audience &write respondentscreener

recruit respondents

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When to Test

Test early. Test often.

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Justifying Usability

Usability is expensive, in time and money. Strike a balance between cost and efficacy. Limit interviews to reduce costs. Testing when the product is already shipping is

the most expensive method: – Formal testing is required.– Results will drive redesign and redevelopment.

Conduct tests during the design cycle. Cost-Justifying Usability.

Morgan Kaufman, 1994.

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Numbers

6 tests is industry recommend. Trends are observed after the fourth interview. 6 one-hour interviews can be conducted in one

day. More interviews yield diminishing returns. Fewer interviews leave open questions. Be careful when documenting:

– Use “some,” “most,” or “all.”– Do not use percentages, which imply greater numbers.

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Types of Usability Testing

One-on-one Co-discovery (two respondents) Accelerated Comprehensive In the office or in a conference room In a facility Paper prototype testing Formal testing

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Facility Setup

video mixer

analyst

video recorder

observers

TV monitor

door

moderator

respondent

one-way mirror

camcorder

microphone

document camera

wireless device

door

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Testing Prototypes Online prototypes lend themselves to facility

testing.– More observers can be present.– Video recording works well.– Observers will benefit from the video monitors—

peering over the respondent’s shoulder would be intrusive.

Paper prototypes lend themselves to conference room testing.– Team members can ask questions following tasks.– Hands-on nature of paper prototyping offsets the

intrusiveness of the setting.– Co-discovery works best, to give respondents a sense

of “community.”

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Respondent Screener Lists of questions that systematically filter out

inappropriate candidates. Define the audience before writing the

questionnaire.Which of the following annual income categories describes you?

I make less than $25,000 per year Terminate

I make between $25,001 and $35,000

I make between $35,001 and $50,000 Recruit a mix

I make between $50,001 and $75,000

I make more than $75,000 per year Terminate

How do you feel about the following industries?

Intense Dislike Dislike Indifference Like Enthusiastic

1 2 3 4 5

Firearms industry

Petroleum Industry

Tobacco industry Must be 3 or higher

Likert Scale

Range

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Recruiting

Often 100 calls yield 1 respondent. Over-recruiting: e.g., 9 for 6. Incentives: cash is king. 50% more for floaters. Send out letters with directions far in advance. Outsourcing:

– Get and check 3 references.– Convenient: they will prepare incentive checks, too.– Manage the recruit carefully:

require re-recruits when necessary.

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Discussion Guide

Provide background information for observers. Introduce the test experience, including

standard disclaimers. Pre-test questions. Include instructions to the moderator in italics. Tasks

– Keep questions open-ended—no yes/no questions.– Include both goal-seeking and survey tasks.

Follow-up questions.

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Audio/Visual Checklist

Video camera Document camera Omni-directional microphone Video mixer Video recorder Television monitor Cables, cables, cables!

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Audio/Visual Setup

video mixing board

observer area

TV monitorone way mirror

video

moderatorrespondent

handheld device

wireless Internet connection

document camera

Internet

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Document Camera

Handheld device

table toptripod

document video camera

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Video Highlights Best done on a digital video editing system

(called a non-linear editor). CDs are easier to use than VHS tapes.

Use a program like PowerPoint. Extremely effective for management presentations.

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