Improving Mobile Website Usability

Amazon offers three versions of its website: desktop, conventional mobile and iPhone.  A recent usability evaluation of the site highlights some of the important issues to consider when designing websites specifically for mobile devices.

The aim

A successful mobile website allows the user to complete their tasks more effectively, efficiently and satisfyingly than when using the desktop website on their mobile phone.

The method

To test the Amazon site, 20 people were asked to search for and then buy a specific DVD.  Half of them used an iPhone on either the desktop or iPhone site.  The other half used a Blackberry Storm on either the desktop or conventional mobile site.  Both devices are touch screen smart phones with (apparently) similar characteristics. 

The results

In general

• The iPhone site and the mobile site were easier to use than the desktop site.
• Users of both devices found the desktop site difficult to get an overview on the small screen and to find the information and links.  They also found it hard to click on the correct link or button.  This was due to the large amount and small size of text, links, navigation and buttons.
• Users testing the iPhone found it more elaborate than the conventional mobile site with more functions and pictures.
• The mobile site was described as too text heavy and too minimalist.
• The iPhone site was best suited for use on a touch screen smart phone.  It allowed users to complete the tasks in an effective, efficient and satisfying way.

What is good about Amazon’s iPhone site?

• Clear and simple page structure helps the user to get a fast overview.
• Fast loading which is an advantage over the large desktop site.
• Only appropriate and useful information is provided.  This is especially important on a mobile site since it is not convenient to scan text blocks for the desired information on a small screen.
• All required functions given to complete the tasks.  (This should actually been taken for granted.  But by reducing the desktop website to its essential functions for the mobile version some important functions could get lost.)
• Logical steps of the ordering process.
• Useful error messages help to recover from errors easily.
• Reasonable input field labels which help to prevent errors and unnecessary effort to recover from errors.  Preventing errors is especially important since each extra click or entry can be a nuisance for the user.

What needs to be improved on Amazon’s iPhone site?

These are some suggestions for improving the usability of the site:

1. Input fields.  Typing a word into the search field or ticking a radio button can be difficult on a touch screen smart phone.  We recommend:

• Reducing the required inputs, for example by ticking a radio button automatically when the user starts making entries in the related input fields.
• Supporting text entries for example using auto-complete text boxes.

2. Navigation.  There was no navigation bar so the user has to use the search field.  Given the lack of space we suggest a limited navigation bar with the main categories such as ‘books’, ‘music’, ‘DVD’ and ‘more departments’.  This would also aid users who just want to browse the site.

3. Content.  Reducing content to essential information is a good approach but can be overdone.  We found one DVD page which contained mainly links requiring the user to click again to get the information.  More content like the synopsis or information about the actors and the director on the product page would save the user time and effort.

4.  Clickable elements.  In some cases the links and buttons were too close and too small so the user clicked the wrong element.  Given that clicking is only possible with the finger and not with a more precise stylus, clickable elements must be big enough and there must be enough white space to separate them.

Summary

When designing your own mobile website always consider:

• The special needs of your users
• The specific characteristics of mobile devices
• The situations in which mobiles are used
• The tasks your user will want to complete.

For information on how System Concepts can help you design interfaces also for mobile devices which are efficient, effective and satisfying to use, please contact us. 

Last updated: March, 2010

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