Smartphone form factor's impact on usability and user satisfaction

Deb Shinder discusses how much a form factor impacts the smartphone's usability and the user's satisfaction (or lack thereof) with the experience.

In a previous TechRepublic column, I stated that hardware design and features are some of the many criteria that you should consider when deciding which smartphone model is best for you. One aspect of hardware design is form factor, which refers to the size, weight, and shape of a device. This time, I take a deeper dive into smartphone form factors and discuss how much the form factor impacts the phone's usability and the user's satisfaction (or lack thereof) with the user experience.

Does size matter?

For many years, the trend in cell phone size was downward. One of the earliest cell phones, the MTA, developed in Sweden in the 1950s, weighed more than 80 pounds. Many of us are old enough to remember the gargantuan bag phones of the early 1990s made by Motorola. These came in a couple of different incarnations - one that had to plug into a car's cigarette lighter outlet to use the vehicle's 12 volt battery, and one that was truly "portable" - as long as you were fit enough to lug around the heavy battery that resided in a shoulder bag. Motorola also invented the first handheld cell phones, which were a similar size and form factor to today's satellite phones.

As other phone vendors got into the game, it became a race to make each generation of cell phone smaller, thinner, and lighter. Motorola stayed in the game, with the super thin RAZR that went on sale in 2005 and became one of the most popular phones of that time. The Modu is a tiny handset from Israel that's about the size of a credit card.

This downward size trend recently went into reverse, however, with the desire for smartphones with more functionality. As multimedia on the phone became possible -- and now popular -- phones started getting bigger again. The iPhone started the stampede toward large touchscreens, but its 3.5 inch display seems downright small today. Two of the most popular smartphones on the market are Verizon's Motorola Droid X and Sprint's HTC EVO, both of which sport 4.3 inch screens and will only barely fit into a shirt pocket. And the Dell Streak takes the prize (at least for the moment) with its relatively enormous 5 inch display, making it something of a hybrid device that falls somewhere between smartphone and tablet.

Some people I know are even dumping their cell phones completely and using their iPads for mobile calling. With the Whistle app, you can make phone calls to any line in the continental U.S. free of charge over 3G or Wi-Fi. There are also low rates for international calling. You get a phone number so others can call you, too. What's the catch? On outgoing calls, you have to listen to a short commercial message before the app dials and connects you, and there are display ads that appear in the app's interface.

Bigger is better... sometimes

There are plenty of advantages to the larger size phones. It's easier for those with "fat finger syndrome" to operate the touch interface and type on the tiny virtual keyboards. GPS maps display better on the larger screens. It's easier to watch movies or view photos. The EVO and Imagio from HTC even have kickstands, so you can set the phone up in a convenient video-watching position.

Another advantage to the larger phone size is the ability to fit in more hardware features. The big phones like the Droid X have hardware buttons for the standard Android operations (Menu, Home, Back, and Search), whereas on some of the smaller Android phones such as the Samsung Fascinate, these buttons are "soft" keys on-screen. A bigger phone also has more room for goodies, such as HDMI outputs.

A large form factor also makes room for a larger battery. One could argue that the larger display will use more power, making this a wash; however, in my experience, the Droid X -- despite its giant screen by phone standards -- gets better battery life after its settings are properly tweaked than some of the smaller Android phones with smaller screens.

Other form factor considerations

Form factor consists of more than the size of the phone. You'll also want to think about other design features (or flaws) that affect the usability of a phone. Often, you'll find there's a tradeoff.

For instance, I really like the sleek look of the Samsung Fascinate and the way it easily slides in and out of my pocket. But holding onto the sleek and shiny phones can be a bit problematic -- it's sort of like holding onto a bar of soap. I've dropped my Omnia II more than once. In my hand, the Droid X feels most secure; it has a less slippery texture on the back that lets you get a good grip, and the slight "bump" at the top not only makes it easier to hold onto and makes it easy to identify which end is up without looking at it (Figure A). Figure A

The "bump" on the back of the Droid X makes it easy to hold onto.
The placement of various controls is another important consideration in using a phone (Figure B). One thing that drives me crazy about the Omnia is the location of the power/display/lock button right next to the camera button. I am constantly turning on the camera when my intent is to lock the phone and turn off the display. Figure B

Button placement can make the use of a phone easier or more frustrating.

The Droid X's power/display/lock button is up on the top edge of the phone, far away from its camera button (which is in a similar location to that of the Omnia II). Then there's the Fascinate, which doesn't have a physical camera button at all. That took some getting used to, but I've come to like that minimalist approach, as I never turn on the camera accidentally.

Here's another factor that phone makers may not give a lot of thought to: placement of the camera's flash. With the Omnia II, it's right in the middle of the left side of the back when held horizontally -- that's right where my fingers naturally want to fall when I'm holding the phone up to take a picture. Samsung apparently learned something, because it put the flash on the Fascinate (Galaxy S, at the bottom of Figure C) at the bottom part of the left end, so that your fingers go above it and don't block it when you're taking a photo. Figure C

Positioning of the flash affects how comfortably you can use the phone as a camera

Is a backlash coming?

Many people seem to be enjoying their hefty smartphones, but some tech analysts predict that the next "big thing" is going to be a trend back toward smaller smartphones. In June, Chris Dannen at BNET said smaller smartphones is a market "ready to explode" and cites the introduction of data caps by carriers, which will make streaming a lot of video and other multimedia activities too expensive for many users. He also notes that better voice command will ameliorate the need for a large virtual keyboard.

The other backlash is represented by Microsoft's advertising campaign theme for its new Windows Phone 7 phones: "It's time for a phone to save us from our phones." The idea is that smartphones have become too cumbersome and that people are spending too much time and energy on their phones. Simplicity was often cited as the iPhone's biggest selling point, and if we do indeed go back to using our phones for more basic tasks -- voice calls, email, text messaging, quick tweets or Facebook updates, playing music -- and offload more complicated activities -- composing or editing documents, browsing the web, watching videos -- to larger devices such as tablets, our phones can shrink in size again. Another point is that if we're going to be carrying around a phone and a tablet, a smaller phone size becomes more desirable.

As for the Windows Phone 7 devices themselves, screen sizes vary. The HTC HD7 appears to be one of the largest, with a 4.3 inch screen to match those of the Droid X and EVO. Many of the announced Windows Phone 7 phones, however, are sticking with a somewhat more compact display (although still bigger than the iPhone). The HTC 7 Surround, HTC 7 Trophy, and LG Optimus all have 3.8 inch screens, and the HTC 7 Pro has a screen size of 3.6 inches.

In a ZDNet article, Russell Fox suggests that in the future the combination of a dumb (and small) phone and a smart tablet may be the best choice for many of us.

Test phones if possible

There are dozens of design elements that go into making a smartphone more or less usable. If you have the luxury, try living with each phone for a couple of weeks to find out its quirks and good points. Some carriers will let you return a phone within 30 days after purchase to trade it in for a different model.

By Deb Shinder

Debra Littlejohn Shinder, MCSE, MVP is a technology consultant, trainer, and writer who has authored a number of books on computer operating systems, networking, and security. Deb is a tech editor, developmental editor, and contributor to over 20 add...