Mobile: It’s not just a city in Alabama anymore (Krug) — DAY 46

It’s chapter 10 of Krug’s Don’t make me think!. This is when the author introduces mobile devices and mobile web browsers. Since 2007, when the iPhone was launched, these devices have been becoming the mains point of access to the internet in the world, as the smartphones have been more and more powerful and responsive. For mobile devices usability principles follow the same, with some important differences:

It’s still all about tradeoffs

In mobile the constraints are even bigger, and the tradeoffs more important. As the author says, usability problems are usually the effect of poor tradeoff decisions.

The small screen

This is the bigger tradeoff. Initially, the approach adopted was the mobile first approach, where designers started to design mobile websites with less features first, creating also another full version for desktops .The whole idea used to look interesting, as designers would have to work hard to prioritize. It didn’t take too long to see that this approach was not really good, as people were more and more accessing from mobile devices and they want to be able to do anything. So the trick is understand what is really priority in mobile, making it easier to the user access, but also providing the other options a few taps away. This actually made websites more and more deeper.


Responsiveness is mandatory nowadays, and you should think about it when you are designing your website.


For mobile, affordances are even more important than for desktop, as the user will need to recognize things without the hover or any other clue. Affordances are the visual clues that suggest that you can use an object, and they should be noticible. This is the last thing you’ll want to take off from your website. The flat design tendency, or even the minimalist design tendency usually impact in affordance. If you’ll design following these approaches this is a very important point to be aware: make it obvious.

Requisites for a good mobile app

They are pretty much the same as desktop websites. Should be:

  • Delightful: related to surprise, to be fun, to impress the user.
  • Learnable: related to be easily figured out by the user.
  • Memorable: related to be easy to remember after some time without using it.

Usability testing in mobile devices

This is very similar, the process is pretty much the same, but the set up is a little bit different:

  • Use a camera pointed to the screen instead of mirroring;
  • Attach the camera on the device;
  • Don’t point a camera to the participant.