Mobile is a magnifying glass for your usability problems. (Josh Brewer)

There are designers and developers and UX researchers out there whose whole world seems to be totally encompassed within the mobile space. Now, that is definitely a fact of life these days. At the same time, though, that’s also a tad unfortunate as well.

For some of these folks, mobile is a brave new world, where they are intrepid explorers creating their own rules. Now, mobile definitely is terra nova. It is not, however, terra incognita.

For someone who’s been doing this as long as I have, mobile is really just the latest whatever. All the things that we learned about green screens, CLIs, GUIs, the Internet … they pretty much all still apply. Yes, there are new things like gestures, but affordances, mental models, proximity, hierarchy, information density, legibility … all that great stuff has not somehow magically disappeared overnight.

Reinventing the wheel is not the point with mobile. In fact, designers need to think, not about being innovative so much, but more about handling the old principles within the additional constraints that mobile involves. 

And what are those? Well, the main one by far is simply the huge difference in screen size. And what does that mean relative to UX? More than anything, I think it takes the old KISS formula and makes it absolutely paramount. Complexity that you might have been able to get away with on a nice big screen is simply going to blow up in your face on mobile.

Less central – but certainly not unimportant – issues include awkward input, new environmental contexts, and several others. There’s also one thing I’ve noticed which probably doesn’t need to be an issue at all. For some reason, some designers took the new context of mobile and decided to just ditch the idea of affordances altogether. 

What do I mean by that? I just seem to see missing pieces on every mobile test I run – or as simply a user myself. In fact, just this morning, I was testing out a prototype for a test I’m running next week on an iPhone …

First, though, I had to clean the screen up a bit, and get rid of some old icons on the home screen. Now, how to do that? Why press and hold those icons, of course (I somehow remembered that from the last time I had to test an iPhone). That puts you into delete mode, where the icons wiggle and have litte x’s in their top-left corners. Okay, this I can figure out – an x is a pretty darn clear affordance. But what do I do to return to normal mode? I would imagine I would press a wiggly icon again. Nope, you press the Home button (had to really think about that one).

Now I can type in the URL of my new prototype. I do that, bring it up, then wonder how I can put an icon for it on my home screen. Oh, it’s the little box icon with an arrow in it (had to ask an iPhone user for that). What do I click now (interestingly, the iPhone user couldn’t help me there). Oh, that little bar of icons on the bottom – looks like I can slide it over (had to ask an iPhone expert for that one). Now, why didn’t they signal that somehow? You know, like with a >, or a little bit of the next icon, or practically anything? 

And all this is before I even get to start in on that prototype. And after that, I then get to try it all over again on an Android, which I least am familiar with, but which also has its own way of doing things, and its own set of affordances to ignore as well. Ugh, it’s gonna be a long day …

Josh was once the principle designer at Twitter