The Relationship

Let’s travel down memory lane. Take a moment to think back when you had your first date. Stop! Just kidding. That’s outside the scope of this book. But, do take a moment to bring up memories of when you bought your first cell phone. For some of us, that journey was a bit longer than others. Even though mine was some time ago, I clearly remember the exact year, the model, and reason why I bought it in the first place.

The year: 1997. College.

The model: Motorola StarTAC, 2G GSM. 4 x 15 character, monochrome graphic display.

The reason: Cool factor! A flip phone, and the smallest cell phone available. I could send and receive calls, SMS, and store up to a 100 contacts. And I could show it off ever so smoothly when I clamped in onto my belt. Back then, that was all of the functionality I could ever want! It was love at first site!

The Break-up

Well, today, that phone is no longer with me, sad to say. I’ve had to keep up with the times and the technology. Since that StarTAC, I’ve gone through an extensive amount of mobile phones. I believe the count total now is eight. That number seems reasonable with the rate at which people get a new mobile phone today – a new phone every 18 months.

Today, my mobile needs of having a device to assist me managing my life require greater interactive control and highly visible functionality on a powerfully, crisp and color display. That original 4 x 15 monochrome graphic display used today, would be quite limiting and unsatisfying.

I’m not ‘Everyman’

Despite my mobile needs, they’re not everyone’s. Mobile design is NEVER about us. It’s about all the other people who are using a range of multiple devices, with varying needs in limitless contexts.

Here are the things we must consider relating to this Screens, Lights & Sensors chapter in order to create an enriching user experience while considering everyone.

Context of Use

One of the mobile design principles centered around this book is that mobile devices must work in all contexts. They must function properly and behave appropriate in variety of environments. Let’s consider the following contexts that can affect the way we interact with the mobile display.

Outdoors

The outdoors is the most complicated environment to design around. It’s highly unpredictable, constantly dynamic, and uncontrollable. External stimuli such as bright sunlight, cloudy days, moon light, darkness, street lights aren’t controlled by the user. We can’t just switch on and off the sun or blow the clouds away. All of these stimuli can make it more difficult to view the screen affecting the way our users interact with the device.

Indoors

The indoor environment may be more predictable, less dynamic, and controllable than the outdoors, but it is still highly complicated. External stimuli present may be natural light from windows, doors, skylights, or generated light from bulbs: florescent, incandescent light, LED, halogen, high-pressure sodium lamps.

Both

Mobile users are constantly transient which changes their environment. They may be using their device outside in daylight to read the news, while then walking inside a public building with dim lighting.

This change affects the amount of time it takes our rod receptors in the back of our retina to respond to light differences. The greater difference between the two environments, the longer it will take our eyes to appropriately adjust. This affects our ability to quickly detect and identify details in that time – such as text, small images, and even controls.

Imagine this scenario: A user takes his mobile smartphone into a movie theater. The lights inside are very dim. He wakes his phone to check the time. The screen display is excessively bright causing him to look away. This is not just a screen display technology issue, it’s a UI design problem.

Here are two solutions:

  1. Have the automatic brightness sensor picks up the ambient light around you and the phone (not your face which typically occurs). It recognizes the low level of light and automatically dim’s the screen to an appropriate level to minimize eye strain and maximize viewability.

But not all users like automatic brightness on…it can rapidly drain the device’s battery.

  1. So as a UI designer, provide immediate access to brightness controls. Rather than have them buried in a system setting, consider using the physical keys (ex. volume) that can open up a menu to control the display settings. These physical controls have eyes-off functionality, and can be interacted with, without even looking at your device.

Displays

Mobile devices displays can range in size, resolution, and pixel density (ppi). As a mobile designer and developer, it’s helpful that you are become familiar with these differences so you can make appropriate decisions throughout the design process. Depending on the requirements of the project, you may be designing for one particular device or multiple devices with varying displays.

Screen sizes

Display sizes vary with the type of mobile device. They are measured diagonally from the display’s corners. Typically, smartphones have larger screen sizes then feature phones. A common misconception with mobile devices is that the screen sizes limit their ability to see the screen.

However, people automatically adjust the visual angle between the device and our eyes. Entirely aside from phones being hand-held, they get moved to the right distance to see things correctly.

Broadly speaking, video display ends up occupying the same field of view regardless of the device size. If we watch a movie on a 46” HDTV, we will distance ourselves enough so we are able to see the entire TV in our visual field. That visual angel can be similar when we view a movie on a phone. This is why people actually do watch video on phones, and will continue to do so.

Other factors that affect how we automatically adjust our visual angle to see the screen include: