I probably should have called this series “How to design mobile software like you know what you’re doing.” since we’ve seen many professional user interface designs fall completely on their faces.
Rule Number 1 in Human Computer Interface design is consistency.
If you look at a Windows Mobile Professional device, you see a Start menu in the upper left corner of the title bar. You’ll see a colored bottom bar with two text-labeled buttons on the left and right sides corresponding to hardware buttons. If you’re in an application, you’ll see a familiar X button that will minimize the application. If you’re in an area that can respond to text input, you’ll see a software input panel icon in the center of the bottom bar. If the contents of an application is scroll-able, you’ll see a familiar and standard scroll-bar on the right side. It’s all very comfortable.
All of the Windows Mobile applications use these same consistent user interface elements. This is very important for both usability and a positive user experience. If I change my Today screen theme, the top and bottom bars may change color. This theme change is reflected in all of the other programs AS IT SHOULD BE.
Lately we’ve seen a lot of user interface designers completely ignore this #1 Golden Rule of interface design, and it is unacceptable. We see application designers removing access to the multi-tasking-essential Start menu. We see applications implementing their own color schemes instead of following the system colors defined by the user. We see software that ignores the existence of softkey menus and disables the software input panels. This consistency rule is not something new, people. It’s been around in Human Computer Interface design for over 20 years.
It’s like going to the Rainbow Room at 30 Rock wearing shorts, sandals and a t-shirt. It doesn’t matter how well you can dance or how artsy that t-shirt is… You don’t belong here! Please go away and come back when you’re wearing a tuxedo like everyone else.
If you see any software developers breaking this consistency rule, please be sure to ask them to come back when they’ve got their application wearing the proper clothing. Otherwise, they’ll never learn, and Windows Mobile will continue to be a laughing stock of usability.
Originally published on Pocketnow on March 19, 2008. More Thought articles from the Pocketnow archive.