Mobile phones have become an essential tool in social and business aspects.
Current statistics show that:
- In 2005 there were 55 million subscribers in the UK
- At the end of March 2005 there were an estimated 61.1 million active mobile subscriptions in the UK, of which almost 90% were held directly by the five mobile network operators
- There is an estimated 140 million handsets/SIM cards in the UK
- In January to April 2006, 30% of households possessed a mobile telephone that could access the Internet
- Research for the last quarter of 2005 showed that 36% of mobile owners used their phones to send and receive picture messages, up from 21% at the same point in 2004.
- Less than 40% of consumers who own a 3G handset actually use it for 3G services
- Around 40 million adults in Europe (around 9% of the adult population) experience problems using mobile telephones
- In September 2007, Britons sent 4.8 billion text messages
- In December 2007, Britons sent 57.6 million picture messages, up 50% on 2006.
- It is estimated that over 2007 a total of 52 billion text messages were sent
- Shipments of multimedia mobile phones in 2008 will exceed 300 million units
- In 2009 it is estimated that there will be three billion mobile phone users worldwide
- Sales of touchscreen phones will hit 200 million by 2011
Problems encountered by disabled people and the ageing population using mobile telephones
Blind and Partially Sighted
The decreasing size of handsets has brought advantages to many users but at the expense of small
keypads, limited sidetone, and small visual displays that people with visual disabilities find inaccessible.
People with visual impairments often cannot locate or identify controls or input slots or operate controls that require sight.
Some people are unable to distinguish between certain colour combinations used on mobile telephone screens and keypads.
Users of hearing aids experience disturbances due to electromagnetic interference (EMI) from digital mobile phones. The rapid pulsation of radio signals from digital mobile telephones can give rise to a buzzing, humming, squealing or squelch inside the hearing aid.
Hearing impaired users cannot locate or identify controls that require hearing (e.g. a voice-based interactive mobile telephone that can be controlled only by listening to menu items and then pressing buttons).
With the advent of smaller mobile telephones, people who have physical impairments may find it hard to hold and activate the buttons on a phone.
For people who are speech impaired, communicating using a mobile telephone in general and speaking clearly to activate functions by voice commands is not always possible.
People with cognitive or learning impairments may experience problems with the operating systems of complicated mobile telephones.
Elderly people can often experience a range of difficulties with mobile telephones, such as those stated above: from the screen being too small to see; incompatibility with a hearing aid and too many complicated specialised functions.
- Good visual contrast between the keys and the body of the phone.
- Key tops should be convex or flat with a raised edge.
- Keys should be as large as possible without reducing the distance between the keys to less than half the key width.
- Ideally the keys should be internally illuminated, but the internal illumination should not reduce the legibility of the numbers in daylight.
- The visual markings on the keys should be high contrast, clear, and as large as is possible on the key top.
- Keys should be raised above the body of the phone (preferably by 5 mm).
- The pressure to activate a key should be between 0.5 and 1 Newton.
- There should be auditory and tactual feedback of key activation.
- Function keys should be tactually discernable from the numeric keys.
- There should be a tactual indication on the '5' key or on a QWERTY keyboard on the 'F' and 'J' keys.
- A voice mode selection that announces all key presses.
- One-touch buttons are provided for ease of calling telephone numbers stored in the memory.
- Provide rotational or linear-stop controls.
- For keys that do not have any physical travel, audio or tactile feedback should be provided so the user knows when the key has been activated (e.g. a toggle swtich or a push-in/pop-out switch).
- There is the ability to switch on or off any buttons on the side of the telephone.
- Where timed responses are required allow the user to adjust them or set the amount of time allocated to the task.
Display / Screen
- The display should have good contrast and use a clear typeface.
- Text should not be scrolling or flashing while it has to be read.
- There should be minimal visual flicker or image flashing.
- Minimise glare on the display and control surfaces.
- Provide adequate back lighting.
- There is the ability to alter the length of activation time for the back lighting.
- The user should be able to increase the font size.
- Text should be in upper and lower case and not all in capitals.
- Use Arabic and not Roman numerals.
- On colour displays, red/green and blue/yellow combinations should not be used.
- Provide colours with different hues and intensity so that coloured objects can be distinguished on a black and white screen.
- On flip-type telephones a good front screen should be provided.
- The SIM card should be easy to insert in the correct orientation.
- The phone should be easy to hold by someone with a weak grip.
- There should not be parts which can easily come off.
- The phone should be able to lie on a table and be operated one-handed (non-slip material on the underside of the phone would help to hold the phone in place if it is used while lying on a table).
- Any external antenna should be robust and not require extending by the user.
- There should be consistent design of the user interface adhering to the relevant standards whenever possible.
- There should be an audio and visual indication when the phone is switched on or off.
- The user should be able to return to the previous state or return to the default status at any stage in the process.
- Error messages should be comprehensible to the non-technical user.
- All labels and instructions should be in short and simple phrases or sentences. Avoid the use of abbreviations where possible.
- Basic functions should be usable without having to use the visual display.
- It should be possible to use the phone one-handed.
- Possible speech recognition dialling for telephone numbers not already listed in the address book.
- There is the option to associate a photograph with a telephone number in the address book.
- The user should be able to set the volume of the ringing tone.
- The ringing/alerting tone should include low as well as high frequencies.
- The user must be able to increase the volume of the audio signal (preferably to at least 90 dB SPL).
- Provide text versions of audio prompts that are synchronised with the audio so that the timing is the same.
- There should be audio cutoff when an external listening device is connected.
- An industry standard connector for headphones or personal listening devices should be provided (e.g. a standard 9mm miniature plug-in jack).
- There is the ability to install assistive technology (e.g. screen reader) directly onto the phone.
Charging the battery
- The battery should be easy to install or replace.
- Provide both an audio and visual indication of battery status.
- The telephone should emit a 'beep' or tactile response when the charger is connected correctly.
- It should not be possible to connect the charger incorrectly.
- The charger should not be tricky to use or difficult to handle (i.e. small awkward parts can be difficult to assemble for someone with reduced manual dexterity).
- An infra-red or wireless port could permit connection of computers and assistive devices. For instance, a visually impaired user could get synthetic speech through their own assistive device; an alternative mechanism is to incorporate speech output of SMS (short message service) as a network facility (this does not tell the user about signal or battery strength which is a function of their terminal).
- Provide connection to a hands-free device.
- Reduce interference to external hearing technologies (including hearing aids, cochlear implants and assistive listening devices) to the lowest possible level.
- Provide a means for effective wireless coupling to hearing aids.
- Provide tactile indication on any plug or insert.
- Provide a bevel around the slot or connection point.
Instruction manuals / Documentation
Manufacturers should provide access to information and documentation including user guides, installation guides and product support communications.
- Use simple clear concise language.
- Have a table of contents and a good index.
- Be task orientated.
- Provide alternate formats (e.g. audio tape, large print).
- Provide alternate modes of delivery (e.g. fax, relay service, TTY, Internet posting).
- Use a typeface with good legibility.
- Information contained in pictures should also be explained in the text.
- Provide information on what to do if the phone does not work correctly, or the user is unable to understand the instructions (e.g. a telephone help number).
Examples of mobile telephones designed for disabled and elderly people
The following mobile telephones include accessibility features of relevance to disabled and elderly people.
- 36 CFR Part 1193 RIN 3014-AA19 (1998) Telecommunications Act accessibility guidelines - Section 255
- 47 CFR Part 6 Access to telecommunications service, telecommunications equipment and customer premises equipment by persons with disabilities
- ACIF C625:2005 Information on accessibility features for telephone equipment
- EG 201 472 (2000) Human Factors (HF); Usability evaluation for the design of telecommunication systems, services and terminals
- ES 201 381 (December 1998) Telecommunication keypads and keyboards: Tactile identifiers
- ETR 029 (1991) Access to telecommunications for people with special needs: Recommendations for improving and adapting telecommunication terminals and services for people with impairments
- ETR 345 (1997) Characteristics of telephone keypads and keyboards; Requirements of elderly and disabled people
- ETS 300 381 Telephony for hearing impaired people: Inductive coupling of telephone earphones to hearing aids
- ETS 300 488 (1996) Telephony for hearing impaired people: Characteristics of telephone sets that provide additional receiving amplification for the benefit of the hearing impaired
- ETS 300 679 (1996) Telephony for the hearing impaired: Electrical coupling of telephone sets to hearing aids
- ITU-T E.161 (2001) Arrangements of digits, letters and symbols on telephones and other devices that can be used for gaining access to a telephone network
- ITU-T P.370 (1996) Coupling hearing aids to telephone sets
- JIS X 8341-4 (2005) Guidelines for older persons and persons with disabilities - information and communications equipment, software and services - Part 4: Telecommunications equipment
- TCR-TR 023 (1994) Assignment of alphabetic letters to digits on push button dialling keypads
- TIA-504-A (1998) Telecommunications - Telephone terminal equipment - Magnetic field and acoustic gain requirements for headset telephones intended for use by the hard of hearing.
- BBC (2009) New phone features 'baffle users'. [accessed 19/01/09].
- Chandler, E. (2006) Mobile devices heuristic evaluation instructions. [accessed 11/06/07].
- Chandler, E., Dixon, E., Pereira, L. M. & Espadinha, C. (2006) A comparison study between a heuristic evaluation technique and end user trial for mobile phone accessibility. [accessed 11/06/07].
- George, M. & Lennard, L. (2007) Ease of use issues with domestic electronic communications equipment. [accessed 10/09/08].
- Gill, J. (2000) Mobile telephony: will future developments be accessible to visually impaired
users? [accessed 07/06/07].
- Nokia Accessibility. [accessed 11/06/07].
- OFCOM (2008) People with visual impairments and communications services. [accessed 10/09/08].
- RNIB (2006) Mobile phones: Owasys is a reality. [accessed 07/06/07].
- Trace Research and Development Center (n.d.) Reference designs for cell phones. [accessed 11/06/07].
- U.S. Architectural and Transportation Barriers Compliance Board (n.d.) Bulletin #7: access to telecommunications. [accessed 11/06/07].
The information contained in this section was taken from the following sources:
- E-Consultancy (2007) Internet statistics compendium. [accessed 21/08/07].
- Glennon, L. (2007) Why can't the phone makers build handsets for everybody? The Guardian - Technology: 6, October 11.
- Mobile Data Association. [accessed 05/11/07].
- Mobile Data Association. Text-it - Latest text figures. [accessed 05/02/08].
- Multimedia Intelligence (2007) Multimedia mobile phone shipments surpass TV shipments in 2008 according to MultiMedia Intelligence. [accessed 04/02/08].
- National Statistics (2007) Use of ICT at home. [accessed 11/06/07].
- Sony Ericsson Special Needs Center. [accessed 11/06/07].
- Trew, Gregory Smith (2005) Starter kit mobile telephone evidence. (PDF) [accessed 11/06/07].
The author would like to thank Fiona Miller for her additional comments and ideas.