Aug 26 - Rainger, Usability and Accessibility of personal digital assistants as assistive technologies in education

Usability and accessibility of personal digital assistants as assistive technologies in education.
Peter Rainger. TechDis, The Sussex Institute, School of Education, University of Sussex, Brighton BN1 9QQ. E-mail: p.f.rainger@sussex.ac.uk
Learning With Mobile Devices: Reserch and Development. a book of papers, edited by Jill Attewell and Carol Savill-Smith. Learning and Skills Development Agency, Regent Arcade House
19–25 Argyll Street, London W1F 7LS. pg 131-138

This paper looks at the accessibility and usability of the devices (from their physical characteristics to the graphical user interface and device controls or input methods). It also
suggests possible uses for these handheld devices as an assistive technology (technologies
for those with disabilities that make studying easier or more accessible).
Keywords: accessibility, usability, PDA, education.


Accessibility and common features of a PDA:
Body (size, shape and weight), touch screen/display and styli).
Hardware design.
Touch screens/displays.
Switches/buttons.
Operating systems/graphical user interfaces.
Batteries.
Expansion slots, ports and connectors.
Docking stations and synchronisation cradles.
User alerts.

Grouped by disability:
• blind and visually impaired
• specific learning difficulties/dyslexia and other cognitive difficulties
• deaf/hearing impairment
• manual dexterity
• mobility impairment
• speech and language difficulties.

Blind and visually impaired
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Features that may hinder accessibility:

small screen size

low screen resolution

small standard font size

short sentence wrapping distance

small touch screen sensitivity areas

poor screen contrast control

poor (font, back or side) lighting for the screen

buttons with a low tactile quality

buttons with small labelling or symbolism.
Features that make accessibility better:

‘live’ text-to-speech (screen reading and document reading)

speech recognition (both text transcription and for 'actioning' commands)

an external screen magnifier
# keyboard commands with navigational prompts.

Specific learning difficulties/dyslexia and other cognitive difficulties
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Features that may hinder accessibility:
• counter-intuitive layout of hardware buttons that action functional commands (eg badly aligned hardware)
• buttons for cursor navigation control
• counter-intuitive location or actions of fixed onscreen buttons
• poor use of symbolism/icons and visual representations of actions or commands
• lack of multimedia options
• poor quality calendar or diary functions that could be invaluable for those with
short-term memory difficulties.
Features that make accessibility better:
• ‘live’ text-to-speech (screen reading and document reading)
• speech recognition (both text transcription and for 'actioning' commands)
• simple graphical navigational aids
• clear menu structures.

Deaf/hearing impairment
--------------------------
Features that may hinder accessibility:
• alerts that are purely auditory (eg a sharp tone when user errors occur)
• complex use of PDA-specific language.
Features that make accessibility better:
• vibrating alert
• flashing LED
• flashing display and/or light.

Manual dexterity
------------------
Features that may hinder accessibility:

holding a PDA for 'in hand use'

type of force or fine touch required to action buttons or other physical controls

small size and/or non-ergonomic shapes of buttons

where stylus or touch screen controls are the only option

small, thin, hard-to-grip styli

poor operating system support for hardware accessories (such as additional keyboards).
Features that make accessibility better:

PDA cases designed with materials that increase friction and grip

an overall shape that allows the device to be held comfortably in the average adult hand

larger, more ergonomic styli that are more easily gripped

the availability of keyboards or other hardware data input devices

speech recognition (both text transcription and for 'actioning' commands).

Mobility impairment
---------------------
Features that may hinder accessibility:

the 'handheld' nature of PDAs, often not toughened

heavy weight

short battery life requiring regular charging.
Features that make accessibility better:

the availability and/or feasibility of mounting brackets for use with a desk, wheelchair or in a fixed location
# a means of portable battery recharging

speech recognition (both text transcription and for actioning commands).

Speech and language difficulties
--------------------------------
Features that may hinder accessibility:

poor use of symbolism/icons and visual representations of actions or commands

poor speech output from written text or picture grids, ie audible text-to-speech

poor-quality built-in speakers

lack of multimedia options.
Features that make accessibility better:

‘live’ text-to-speech (screen reading and document reading)

better in-built memory to cope with speech output.


The following lists uses that could benefit people with a range of disabilities (or none):
• note taking – using a text editor or word processor for taking notes (in most
cases this would also require a peripheral keyboard)
• viewing/storing reference materials – using a customised PDA database, text
editor files, or e-book/e-doc files to store and present information (such as sections of a textbook, old essays, lecture notes, etc)
• diary planner – using an electronic diary and planner for an academic timetable.

The following application types can be useful for those with short-term and working memory problems:
• reference databases
• electronic material readers (e-doc readers, text editors and word processors)
• electronic reminders and user alarms
• to-do/task lists.

The following application types can be useful for those with time management and organisational difficulties:
• to-do/task lists
• diary planners/calendars
• electronic reminders and user alarms.

The following application types can be useful for those with difficulties with writing skills and structuring thought processes:
• outline tools
• mind/concept mapping
• text editors (or word processors, for note-taking).

The following application types can be useful for those with problems with spelling and grammar:
• spelling checking software
• spelling correction software
• reference dictionaries (including language conversion) and thesauruses.

The following can be useful for those with auditory and visual impairment or processing deficits:
• text-to-speech (auditory feedback)
• Rapid Serial Visual Presentation (RSVP) (where each letter of a word is briefly shown in sequence).

The following can be useful for those with concentration (including tiredness and fatigue) or attention difficulties:
• multimedia electronic documents
• text-to-speech (auditory feedback)
• RSVP (as above).

The following can be useful for those with difficulty in multitasking and physical coordination or dexterity:
• remote computer control
• remote environmental control (through the use of an infra-red controller.

The accessibility of a PDA can be viewed from two perspectives:
• The accessibility and usability of the PDA device
A person with a severe visual impairment may find it difficult to read the comparatively small text on a PDA display and may find the information it presents inaccessible thus making the device unusable in its original form.
• The use of a PDA as an assistive technology
A person with a time management and organisational difficulty might benefit from the diary and calendar functions of most PDAs which would thus provide functional technology assistance to someone with a disability.

References that I may consider to read more in the future:
The project website ‘Usability ad accessibility of PDAs in education’ can be found at:
www.techdis.ac.uk/PDA, accessed 11 November 2003. Rainger 137