The Practice of Mobile UI Design

Mobile UI design is fundamentally the same profession as desktop UI design, but that doesn't mean that the skills transfer or that a desktop UI designer can turn out a good mobile UI.

In many ways, it depends on what sort of research you do. If you spend several weeks understanding your users when they are mobile, then another few weeks studying exactly what is and is not possible and useful in mobile technologies, then you can do a pretty good user interface for mobile even if you had no previous experience.

It's difficult enough to understand the technology ("what do you mean it doesn't render on that phone! it has the correct browser/MIDP/screen size!"), but understanding the users is more challenging.

So many portions of design practice are rules of thumb, unless you are very rigorous (read: "willing to spend time and money"). In the desktop internet world, there at least used to be the "8 second rule", in which you wanted your page to render in 8 seconds (down from 10 seconds, and a far cry from common practice).

What is the corresponding rule in the mobile space? Why? Or does it vary?

I find myself telling my phone to fetch something (email or internet), then continuing with my real-world activities for a few moments. That's fine, unless I'm in the middle of a process. But if I launch a J2ME application, I do not want to wait even 5 seconds for the application to launch!

When I made the transition from desktop design to mobile design, I had to understand an entire new universe of users - one that is evolving more quickly than computer users, and varies across continents more than computer users. And I don't see most designers even realizing this process is necessary.