Touch Screen Phones Usability Problems Computer Science Essay

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Touch screen computing devices such as the iPhone are becoming more and more common these days. However this technology is largely inaccessible to the people with visual impairments. Use of one-handed thumb on the touch screen of smart phone or touch phone is considered as an effective alternative than using a stylus or index finger, to set the other hand free performing supporting occupational activity. Usability research and experiments are performed for better understanding the role of fine motor control, thumb usability acting as a tool to interact and the ergonomic user needs. Design recommendations are made for improvements in terms of overall effectiveness of smart phone usage with one-handed thumb. It is also to benefit people like semi-literate and illiterate users.

Latest mobile phones are designed to enable users to access a wide variety of information and communication services at any time and place. There are problems linked with these devices which may get worse when attempting to use them in a crowded, noisy or distracting environments etc.

It is quite infrequent to see only 10 years back, today people belonging to all ages, professional backgrounds and skills use mobile phones on daily basis. As time passes by not only mobile phones are becoming pervasive, they are also equipped with features like e-mail, web surfing, and global positioning system(GPS) aptitude, as a result of which providing access to additional information and services at the same time. This information is very useful to most of the users, however it may be of very importance to some users having disabilities. For these users, mobile phones are a tool to connect to the friends, family and caregivers, making them independent, and act various actions and interact with the world while remaining connected to the necessary support and services. With the presence of latest mobile phones different type of usability problems arise for the users. Also these phones are inaccessible to people with disabilities and users of visual impairment may come across difficulties around using these devices because of issues like controls that are difficult to manipulate. In addition, as mobile phones are used in a number of situations, such as walking down the street or riding public transportation, environmental factors such as ambient noise, unsteady surfaces and weather conditions that may further add to the user's ability to interact with the device.

Although mobile phone accessibility issues may be interchangeable by environmental factors, understanding the effects of these factors makes it possible to develop user interfaces that can adjust to these restrictive situations, as a result of which increasing the overall accessibility.



As the number of mobile phones are out-shipping the traditional computers by more than 4:1 in 2006,

The emergence of the mobiles as an ever-present personal accessory is clearly visible. The mobile phones have served a little more than wireless telephones in the past and mobile information management had been limited to PDA's and laptops. With the express improvements in the processing, storage, capacity and connectivity, these various devices types are converting into "smartphone": a multi-featured, internet enabled mini-computer. As the number of these such devices is growing so as the opportunities to explore a wider range of interaction methods, as an example of which is Apple's touch screen iPhone. Due to the mobility as a driving factor devices will continue to be small and portable. In these diverse mobile environments users are bound to such visual and mental distraction having one or both of their hands occupied frequently. Keeping in mind these trends, today's touch screen software designs are often not doing a good job in supporting mobility, as most of them demand a two handed stylus input.

Interfaces that allow single-handed interaction can offer a significant benefit by allowing one hand usage for the physical and intellectual demands of mobile tasks. Surveys have been carried out which confirm user's general preference, having able to use touch screens with only one hand when possible, however today's hardware and software designs normally don't offer such support. Interaction with touch screens generally requires the use of a styli as the software interfaces of the touch screen mobiles are made up of targets which are either too small or badly positioned making them very hard to be hit easily with the thumb. There is however a solution to this problem to build interfaces that clearly accommodates thumb interaction by making it sure that the entire target locations are thumb sized and easily reached by thumb. This "Lowest Common Denominator" approach to interface design is not likely to catch on. Answer to this is that small screens already are so rigorously holding back information presentation that if further limits are applied on the visual expressivity can change the design in various ways. As an example, if we increasing the target size to hold the thumb could end up in a few targets being shown on a single screen and it would require additional screens to show the same amount of information. It can slow down the access to information, even being used by two hands. Analysing these observations along with the reality that are being used by the current mobile User Interface toolkits which include only little stylus oriented widget palettes, which leaves us with nothing else but to consider an alternative strategy.

With the dynamic environments and diverse tasks of mobile computing, preference of user about the number of hands to use is expected to be fluid. Therefore effective mobile interfaces will therefore focus in maximising presentation power and interaction efficiency despite of hands availability. With Thumb Space, touch screen devices can continue to take full benefit of the real estate available for rich presentation and interaction with both hands having one handed issues being taken care of at the same time. The design and implementation of Thumb Space is given below. The assessment of Thumb Space as compared to direct thumb interaction for accessing targets of changing size, density and location.


The physical and attentional demands of mobile device use were reported early on for fieldworkers. As a result of which specified design suggestions for least attention and one-handed interfaces which were thought to be customised to the needs of the fieldwork, did not simplify the wide range and complex personal information tasks of the common users. Since then, research in single-handed gadgets interaction has put up huge attention on either the hardware or the tasks supported.

The potential benefits of accelerometer augmented devices and touch screen-based gestures [for one-handed interaction have been investigated by technology-oriented efforts. Other research has focused on enabling one-handed support for precise tasks, including media control and text entry. But in general, there has been comparatively little focus on thumb interaction.

Karlson et al. looked more deeply at human factors requirements for one-handed interaction with personal mobile devices, including situational and task preferences for hand use as well as biomechanical limitations of thumbs. It was found that in addition to the common practice of one-handed phone use, there is wide interest in single-handed use of (generally larger) touch screen-based PDAs, but that current designs do not accommodate one-handed scenarios well. Their results further suggested that users were more comfortable when interaction could be limited to a sub-region of the device surface, preferably toward the centre of the device.

Thumb Space's design addresses these findings directly. Various studies have been carried out on the physical characteristics of the thumb interaction with the touch screen technology. Parhi et al. investigated the effect of target size on input accuracy when operating a PDA one handed with the thumb. Earlier to that, others had determined appropriate target sizes for pen-based interaction on mobile touch screen devices, and index fingers for interaction on desktop-sized displays, however pens and index fingers are far too smaller than thumbs and their use scenarios differ from mechanic constraints of holding the screen with the same hand used for interaction.

Touch screen interfaces used today consist of widgets similar in size and functionality to the ones used on a desk top PC. Although valid to be used with a 1mm stylus tip, however these targets are much smaller than the usual thumb pad at least in one dimension, which makes reliable access difficult or impossible. Previously, the Shift technique was presented as an improvement by Vogel and Baudisch against Sears and Schneiderman's offset cursor, both of which address concerns of occlusion during finger selection of small touch screen targets. Shift as being a huge potential for the selection of the targets by one hand within the reach of the thumb. In order to understand if pixel-level selection is effective under mobile conditions further investigation would be essential, and if Shift works equally well for the objects around the borders of the screen which is quite common in the designs today. An important thing to keep in mind that Shift was designed for both hands index finger operations of the mobile devices, apparently does not deal with the limitations of thumb reach that Thumb Space tend to address.


Thumb Space illustrates its stimulation from the observation that large table-top and wall sized displays both come across issues with out-of reach interface objects. Increase in the real estate also increases the average distance between on-screen objects. According to Fitts' Law increasing travel distance without a corresponding increase in target size will increase access time. Therefore solutions have generally emphasized on

1) Decreasing movement distance to targets and/or

2) Increasing target sizes.

We classify these further into indirect and direct interaction methods.

Indirect Interaction.

Improving target acquisition for mouse-based interaction has often involved clever manipulation of the control-display (CD) ratio. Slowing mouse movement over interaction targets (Semantic Pointing), jumping the cursor to the nearest target (Object Pointing), and predicting the user's intended target (Delphian desktop) are three such examples. The drawback of these techniques is that their effectiveness decreases as the number of nearby objects increases. Other approaches in smart cursor control make targets easier to hit by increasing the cursor size, such as area cursor and Bubble Cursor.

Direct Interaction.

Direct screen interaction with fingers or pens is common in tablet, mobile, and wall computing, the absence of a remotely controlled cursor means there is 1:1 correspondence between motor and display movement, and thus no cursor display (CD) ratio to manipulate. Since increasing target widths has generally been achieved via CD manipulation, techniques for direct input have focused on reducing the movement distance to targets. Drag-and-pop reduces an object's drag distance by drawing full-sized proxies of targets closer to the moved item. The Vacuum widget allows users to select the display sector of interest before moving object proxies to within reach. Drag-and-throw and push-and-throw reduce movement distance by virtually extending the reach of the finger or pen. A final class of direct interaction techniques offers users miniaturized, nearby versions of the entire display area for manipulating distant objects. With Radar View, the miniature representation appears as users begin drag operations. The Bubble Radar extends the Bubble Cursor to pen-based computing, using a Radar View representation and dynamic expansion of the pen's activation area. Thumb Space uses a similar approach to the Radar View, while addressing occlusion and small displays.

Thumb Space

The goal with Thumb Space has been to develop an interaction strategy whereby rich touch screen interfaces can be effectively controlled with a thumb, without sacrificing the expressiveness of information presentation or the efficiency of navigation when two hands are available.


As many mobile phones are difficult to use for people with disabilities, these people may come across additional accessibility problems when trying to use a device in a busy environment or while moving. As an example if a button on a mobile phone is difficult to press while sitting at a desk will likely be even more difficult to press when the user is on a moving train or is walking down the street. This negative effect on performance caused by environmental factors can be considered as a situational impairment, since it effectively impairs the user's ability to interact with the device. Situational impairments may affect mobile phone users with and without disabilities. Situational impairments can be as a result of a range of factors, including user movement, inclement weather, impeding clothing, or user fatigue. User performance is affected by these impairments in various ways, including reducing reading speed and target acquisition speed. Custom interfaces that can are designed to integrate into user needs may reduce the effects of these situational impairments. In order to overcome the effects of situational impairments through these situational adjustments user interface needs to be adapted to be used in a certain situation. For example, a user interface might make text larger while the user is moving in order to make it easier to read, or might increase text contrast when the lighting conditions are poor. These adjustments may be triggered automatically when required, as a result reducing the effort required to interact with the device in a distracting or impairing situation.


In designing a conventional electronic device like a mobile phone, its characteristics such as the position of the controls are permanent and cannot be changed after the production. Any kind of application that runs on that device must be tailored to fit and work in compliance with the characteristics set in the first. However, there is a different kind of approach used in the touch screen devices as the positioning of the controls is a dynamic feature and can be modified as custom user needs depending on the application parameters on which the device is running. Keyboard on a phone is designed for use while making calls, having a more suitable interface created for audio and video playback facilities. In a discussion held on the topic of appropriate vs. assistive technology, mainly it was discussed that many of the today's mobile phones had very little controls, or it may be the reason that they liked the Daisy music played due to its large controls. If only advantages of touch screen devices are looked at , the preference would be to create an interface with large buttons as an alternate for visual impaired people, in addition to a more conventional interface having dedicated features like contact pictures and visual interaction that a sighted user would wish. If allowed it would reduce the need of low numbers of expensive, yet desirable devices, like Daisy player. In simple words the difference between two conventional technologies, assistive and appropriated mainstream, can be reduced, having the dedicated interfaces being produced to suit both kinds of users. There is however a problem with this approach as how a visually impaired person can interpret the controls. The buttons and various other controls on the touch screen cannot be felt in the same way as a real physical control. This is where a lots of problems start for the people with visual impairments and the interaction with touch screen.



Attention Diversion

Today's touch screen phones are equipped with so many attractive features and due to their demand in concentration a user is almost or sometimes completely lost in it and does not know much about what is going on around him/her. It is a very potential problem faced by many people and increasing as number of touch screen phone users rise. It has led users into various situations out of which a few are mentioned.


Many of the accidents occurring nowadays are due to the use of phone while driving and due to the touch screen the numbers have increased. It is not just the mistake of people driving the vehicles but also the ones on the road walking unaware of the world around them.


An ever growing field as technology advances and portability gets better and better. Due to the increasing number of people using mobiles while walking, in busy places, on public transports, while driving etc unaware about the eyes watching them theft has increased and features in these mobiles make them quite tempting to sell after stealing.

Listening music

One of the issues that came up with previous phones however it increased at a huge rate after these tocuhscreen releases of the phones which give more interactivity to the users. This has caused issues at public places especially at public transport places causing a disturbing atmosphere while listening at a high volume. It has brought up concerns about the health issues. Constant listening can be quite harmful to the hearing and become a potential risk of hearing loss.

Eyesight related issues

Another key issue is the ever increasing use of screens. With the use of screens in everyday life is a concern for the eye sight. Along with the various other screens used on daily basis the growing amount of screen usage can be a possible risk to eyes in the long terms. Even though small in size, the excess use is an important factor to the eyesight problems.


Mobile phones are used by people of all ages. However with the people with older age come accessibility and usage problems. The mobiles today are build on standards, most of them are equipped with very less or no support for old people. It is very hard to put everything in a box, but to tackle with these kinds of situation the design should be kept open to be updated by time and as per requirements.


Mobile phones are becoming very popular among the teenagers however as technology is getting more and more advance the safety risks are becoming more distinctive and worrying.

Threats to Teenage Safety

Among the various common issues in happening nowadays, whether it is theft, bullying, health risks, scams, grooming etc, it is hard to believe that such a small and harmless gadget like the mobile phone can cause a wide range of possible dangers to the teenagers. More to this is that it being so simple and portable has become very hard for the parents to protect their children against the so forth threats caused by mobiles.

There was a time when parent's main concern was thought to be mobile theft and bullying and they only permitted the teenagers to use mobile phones as for making calls to one another and SMS messaging.

Mobile Bullying and Theft

Bullying has entered into a new era and SMS messaging has given it a new name. SMS messaging has opened new doors for it and brought it into the 21st century because twenty four hours accessibility of mobile users indicates that bulling is no longer needed to be done in conventional way. One does not have to wait outside the school gates to look for their targets however they can track them at any time. It has turned into one of the biggest safety issues about the use of mobile phones by teenagers because of the damaging psychological impact on its victims.

Parents are advised to encourage their children to discuss about any kind of problem they might be experiencing so that the problem is not left unattended or ignored where it may grow and cause much more damage. In situations like where mobile bullying continues to grow and its time span is increasing the first priority is to contact the mobile phone operator and reporting them the problem.

Abusive calls - landline users are quite known to the stress of bullying on the phone. It also poses a danger to the mobile users of teenage, who could be facing threats of violence or regular frightening silent calls. If the police or the service provider is informed about it and complain is made then these calls could be traced, even though it can prove quite difficult especially if the person behind is calling from a pay as you go phone without any record of their identity.

Risk of Theft

Mobile phones, being one of the desirable items. The desire continues to increase as their capabilities grow. Theft is always going to be a major problem, however with children it is even more obvious because, as statistics reveal, children are more likely to the victims of the mobile phone theft. In case of a young teenager's mobile phone is stolen it should be reported straight away. Additional precautions should be carried out and it is advise to keep the phone protected with a Personal Identification Number access. This protects the stolen mobile not to be misused by preventing the access.

New Technology, New Phone Threats

Mobile phone technology is progressing at a exceptional rate, it introduces ever more exciting new features, however they don't come alone. It comes with a whole series of dangers especially for young children. One of them takes the advantage of the phone's feature to make video calls, and grooming, a much known danger for the internet users which has now spread to the internet-enabled mobiles.

Health Risks

Having these associated risks in the mind it also advisable to look at the risks related to the health with the use of mobile phones. There have always been concerns about the health with the usage of mobile phones. Although there have not been an evidence of such incidents however we it is important to bear in mind that low level of radiations are emitted by mobile phones and children are more likely to be affected as they are three times more likely to get it.

A scientist warned that if mobile phones were some kind of food then they would not be licensed because of great doubt about their safety. If hence it makes sense to the parents should carry out some cautious approach in overlooking their children's mobile phone use. As an example children should be advised to text instead of calling.


Through evaluation we have come to know that how much work is there to be done in touch screen technology in terms of accessibility especially for the ones with visual impairments. Some kind of overlay needs to be placed between surface of the touch screen and the user's interface in order to use control panels like buttons. As research showed that PDA did not make problems, while position is detected by the physical being applied on the screen while other technologies using touch screen positioning techniques(s iPhone) may not work accurately in a case if there is an overlay between screen and user. An approach recommended by a visually impaired person to "inverting" the control panel in which buttons are dug in instead of raised ones, may help in this scenario, however further investigation is required to decide the usability of a control like that.

As an addition dealing with the buttons, user is required to carry out a tangible overlay. It has been discussed already how overlay's presence is taken by the system, however it is still an important thing that needs to be supplied and carried around. An overlay technique is more likely to become impractical if a new style of control panel is required by every interface.

As a conclusion in the entire cases visual touch screen interface needs to be tailored to facilitate the need of a visually impaired user. It can be achieved through some physical modifications to the device. It indicates that it would become possible in the future to have a single device designed to fulfil the needs of both kinds of users.


As technology is advancing and new approaches are being used to tackle the current issues and with the innovation in IT sectors not just providing the world with new and improved technology but also capability to overcome previous issues.

A method of interaction technique is in development phase for influencing comparative information regarding the user to minimise accessibility issues during mobile use. Numerous types of contextual information can be sketched under these techniques, which include the location, movement and current activity of the user. Sensors on the mobiles can be used to gather information required. User performance can also be monitored through this system, and can take appropriate steps in the scenarios when user performance is considerably less than a set limit. Let's take an example of a situation where the user is pressing the BACKSPACE key a lot more than usual a take it as user facing difficulty in typing. The user will be allowed to put in place custom preferences to get use to the interface. On the discovery of any possible accessibility issue, the user interface can adapt to allow more accessible interactions.

The illustration of this system is given in Figure 1.

The proposed system consists of three primary components.

The system must establish the situational occupation of the user with the help of sensors on the mobile phone. It has been revealed through former research that it is likely to establish the location and movement of the user with the help of on-device sensors. A model of user's activities and capabilities can be created with the help of data retrieved from various sensors.

Secondly, it is mandatory for the system to present an array of interface alterations which can deal with the accessibility issues as they occur. A number of shapes may be taken by these alterations, which include:

Resizing or rearranging a user interface to overcome interaction problems,

Automated performance based on situational scenarios to minimise the efforts required,

Activating a substitution interface that is customised to the given scenario, or

Triggering error correction for minimising pointing and typing errors.

Examples from various common scenarios of mobile use, their possible situational impairments and solutions to overcome these impairments are given in Table 1.

Finally, as each user is different from the other and their needs vary, the system must be designed to allow users customise accessibility features to fit their needs. Users should have to control to select from accessibility features which suit their requirements, and decide when they will be activated. Also users may also be able to advance customise the alteration like selecting the minimum and maximum sizes for onscreen targets etc. These customization features must be designed in order to be easily used and accessible to people with a range of abilities.