Let’s analyze the reason for this:
•Sharp increase in the count of people accessing Internet from Mobile
•Platform used to access site is less predictable when using mobile phones. Computers differ in terms of OS and browser where as the difference between mobile phones and PDAs is wide.
•People have less experience using mobile to go online than computers.
The next big hurdle is how we narrow down our choices for mobile phones and PDA when we have hundreds of them around us. Some of the prominent ways in which mobile devices differs are:
•Screen Size (Large Vs. Small)
•Screen Layout (Landscape Vs. Portrait)
•Pointer or Input Devices Used (Stylus / Numeric Keypad / QWERTY Keypad)
Ideally testing should be done with maximum number of devices so as to include a wide range. But testing with every device is not possible. So we can narrow down the choices of devices based on some factors:
•Popular Mobile Phones in that Geography
•Audience of the site. Certain age group of audience tends to prefer particular types of phones e.g. phones with large screens to support easy online access.
•Targeting Phone families that offer similar UX
So this basically addresses questions like why we need to do Usability Testing and narrowing it down to how do we pick the devices for the same.