Usability Tools

The objective for this task in the studio is to decide how far and in what ways Usability Goals and Design Principles have been used in the design of a mobile phone. The mobile phone that will be analysed is the Samsung D900 (FIG 1).

FIG 1 – Samsung D900

What are Usability Goals?

Usability goals are defined when building or designing technologies. It is a measurable design purpose relating to how functional a system needs to be. The six usability goals will now be applied to the mobile device which target specific scenarios and functions of the phone.

Effectiveness

The Samsung D900 is very far fetched in terms of how good the phone is delivering for what it is suppose to do. It has many useful features and functions that give satisfaction to the user of what an advanced technology phone should do. It has features such as, Java games, a 3.15 Mega pixel flash camera, Bluetooth, EDGE/GPRS WAP network technology, photo editing expandable memory etc,. It meets the needs for what the device should do as an advanced phone and for the user. As explained acceptability fits in with the people’s ways of working and is productive since it designed to be a human centered device.

Efficiency

This device supports the user in carrying out their tasks in a very well-organized and structured way in terms of shortcuts and easily accessible functions on the mobile phone. The device has an external button short cut which allows the user to, click to take a photo, increase and decrease volume on speaker/keypad tone. It has a quick launch button which allows the user to search through their contacts in alphabetical order while giving the user power to search and find selected contact directly.

The user can also man quick phone called by finding contact or using the hold down keypad button to phone in a single key process. While to user is on the phone, he/she can make effective use of the device itself giving more that one functions to carry out at one including, sending text message while on the phone, looking through phonebook, looking at o2 services. Etc. This device allows the every-day usage of the phone to be well-ordered on these ways.

Safety

The D900 Samsung device is a safe phone to use to an extent. You will not get any electric shock from but the common issue in radiation is an issue but that is not a heavy problem in this case. There is the issue of the battery overheating if you leave it in certain conditions but this is up to the user to be aware of this common sense realization. As a device the internal protection is very good as it allows you do put passwords on anything menu or folder you want which gives the user great confident in the breach of privacy.

The device is reliable in giving the user frequent prompts when he/she is making a permanent change to setting or action of the phone i.e. canceling a message it will prompt ‘ok, back’. If the user accidentally presses the red phone button while creating a message, it will prompt the user to save it to draft folder. Once the phone is closed, slider closes; this automatically locks the phone and makes it safer in terms of accidental keypad actions. But there is still a safety issue where the user can accidentally press the right sequence of buttons to deactivate the keypad and make unexpected actions i.e. phoning someone.

Utility

The device allows the user to perform many actions with simplicity like the phone side buttons when the user can take a photo in two step by opening the application and taking the photo. Also, there are two up/down button which enables to user to directly changing the volume, scrolling/paging down a menu. Listening to music via the built in Mp3 player, viewing PDF, PPT files to view documents which can be utilized very effectible.

A limitation in terms of make the most of out the device would be how the user can’t randomly selects menus for example since they have to use the keypad to move up, down, left or right in a number of sequences. A solution to this would be having a touch sensitive screen which makes all operation of the phone allot easier and time consuming.

Learnability

Learnability is a key principle in the design of any mobile phone. In this can The D900 (FIG 1) is relatively uncomplicated in providing the user to understand quickly where things are located across the device. For example, the menus are structured in a way the user can categorized itself where the function might be where for what the user is looking for and in general this can come to terms of common sense relating to how the D900 phone is structured. When using an mp3 player to user can relate to other devices like a computer, laptop, PDA, or mp3 player. It clearly has stop, play skip buttons displayed. The phone offers informative feedbacks showing prompt and strives for consistency which makes it easier to learn how the phone operates.

Memorability

There mobile device incorporates many ways to able the user not to forget how the device is used in terms of remembrance and consistency. Firstly the design interface is structured in a very consistent layout using the same colour scheme and menu structure throughout the phone. The menus are divided onto separate categories and in certain rows/columns that the user will remember after use it a couple of time. It will soon be natural for the user to automatically understand what buttons to press (up/down/left/right or keypad) to get to the outcome.

When the user takes a photo, it will save it into the photos folder. The menu shows blocked icons which clearly pictifies what the menu will consist of. So it gives the user understand and remembrance of what it is before the user clicks on it and after the user used the feature.

What are Design Principles?

Design Principles is like a set of guide lines which direct the designer during the design process. This can be incorporated to evaluate and analysis prototype designs in this case, the Samsung D900 mobile device will be evaluated under the six principles that was introduced by Don Norman.

Visibility

The D900 enables to users to see what functions are available and what the device is doing when these functions are in use. The keypads are clearly defined and labelled again to an extent (FIG 1). The top two main buttons just have three dots on them so it isn’t very visible to the user to understand the function for the button. But when you look at the screen, it clearly shows the description for them which is menu and contacts. This is placed above the buttons on the bottom of the screen so it does do the job when you look at the screen.

It has a cancel button defined as ‘C’, it has two phone button, the green phone meaning pick up, and red phone with switch of button meaning, put down/switch off/cancel all actions and return to main screen desktop. The phone gives the user to recognise keys and functions instated of recalling what they mean or where to find it. In addition visibility in also included through the use sounds.

Feedback

The Samsung D900 device gives the user quick feedback informing the user what effect their actions have had. When the user us sending a message it clearly says ‘Sending Message’ and when it is sent is prompts, ‘Message Sent’, also giving you the option of cancelling. Feedback is shown in different forms through sounds and visual display.

When the user sends a message or makes has a correct outcome it has a high pitches sounds and when it isn’t it has a low pitched dull sound. When a user deletes a message, image/video/sound file, they are always prompted to confirm their actions. With the device frequent feedback this will emphasise the concept of the user feeling in control.

Constraints

This device was made so that it prevented user from trying to do things that are inappropriate. This givens the user restricted access to options and results in a reduced chance that the user will make a mistake. A physically example is that the memory card, charger and headphones can only be slotted in one ways. Also the keypad can only be pressed down instead of being pulled or sided to have a result. So this prevents errors happened but giving a result due to this constraint.

The logical constraint for this device is how selected menus options are disabled when it is not appropriate for the task. For example when you select wallpaper, you have two options for have a built in wallpaper and your own wallpaper. When you select normal this allow you to get your wallpaper and you ave different options for this. However if you chose the theme wallpaper option, all the other options are disable since it is a built in configuration. As a result the other disable options are shaded grey to notify the user of their constraints or limitation.

An example of a cultural constraint is when you delete a message; a red question mark will appear saying ‘delete –yes or no’ which symbolises danger which alerts the user of something that will be permanent, or something that will make a significant different to the functions or actions. The same applies to when the user types the wrong password in, it had a red exclamation mark for this action.

Mapping

The mapping on this device isn’t very understandable. It is easily acknowledgeable for people who have an understanding of the layout. For example, there are two buttons which that there dots on them. That doesn’t show what it’s for. In the centre of the top keypad it has a four way navigation (up, down, left and right) movement which shows no mapping jus a plain face and not even a shaped indentation to show grip. This isn’t very clear. There is a centred button showing ok/i. User will easily map this to its functions. On the screen through various menus, it has different functions for the two top left and right button of the keypad. Also for the mp3 player it has clear play, forward and stop button to map its function.

Consistency

This device is definitely consistent through its physical design features and its standard ways of working. The menu structure and design are consistent throughout giving the user ease of use and understanding how things will operate similarly. Also the red phone button will always cancel what you are doing and take you to the desktop after a prompt. This is consistent through all operations.

Affordances

The design of the phone is clear in what they are for. For example allot the button on the phone afford the user to press or push them. The user will be aware of this since it is raised 1 to 2 mm which gives the user understanding. There is a micro SD slot on the side of the phone which is flat on the phone. It has a indentation on the side of it so it will afford the user to put its nail or finger n it and pull the cover off.