PC vs. Mobile

1. Screen

Screen size and resolution present the most visible and obvious challenges for mobile devices. Screens have become larger in recent years, but they have pretty much reached the limit on what makes sense for a mobile device. Any bigger and the device becomes unwieldy. Until folding displays and other future innovations come readily available, designing for a mobile device is designing for a small screen.

In practice this means there is always a very limited amount of space for the user interface elements. It isn’t a problem to show 20 icons in five groups when you’re working with a 23-inch high-definition wide screen on a PC. It becomes a problem on a 2-inch screen with 240 x 320 resolution. The interface must be limited to a few simple objects that are big enough to see from arm’s length.

2. Input

Device size limits the size and variety of the input mechanisms. After the screen there is precious little room for input controls on the device. Even with touchscreen devices the screen itself is limiting, and the onscreen controls have to be large enough for a finger or stylus.

There is no mouse. Most current mobile devices rely on a few action buttons and a directional five-way “rocker.” Design that requires smooth, fast, and accurate movements will not succeed. Touchscreen devices are exceptions for this rule in some cases, but even then we’re talking about touch, not a mouse.

Most of the time there is no full QWERTY keyboard. If there is one, it’s very small. The simple fact is that a keyboard or keypad on a mobile device will not be as pleasant or fast to type on as a full-size keyboard anytime soon. Therefore mobile users should never be forced to enter long strings of text during use, unless it is absolutely mandatory for completing the task.

3. Mobility

A mobile device is, by definition, mobile. From a usability standpoint the most important thing about mobility is that the user can be anywhere, from a quiet office to a crowded store to a fishing boat on the open sea.

This should be taken into account when designing a product, be it a Web page or a full-blown application. In general, never assume that the user is in a specific place, even though it might feel like a reasonable assumption. For example, if the product is a Web site selling ringtones for teenagers, it’s fairly reasonable to assume that the user is not in a noisy, dark steel mill. But the user may be at a party, which can be just as noisy and dark.

Screens should be tested under different lighting conditions, and sound should never be relied upon as the sole notification method in mobile applications. Often an environment is too noisy to hear sounds, and users frequently turn them off. Also, making the user interface elements clear and keeping controls simple help when users are in motion.

4. Connectivity

Wireless 3G broadband is growing in popularity, but it pales in comparison with the network speeds of desktop computers. Mobile devices can handle less data than a PC, and this should be taken in consideration. Too-large downloads force users to wait, which can be very annoying if they just want to perform a quick checkup. Mobile applications and sites should be streamlined to use as little bandwidth as possible. A picture that loads in an instant on a PC with broadband might take quite a bit longer on a mobile device.

Also, mobile connections are not as stable as a cable on a PC. For example, a user might be on a train that goes in a tunnel and gets cut off from the network. Good design ensures that a sudden break in connection doesn’t result in data loss or other problems.

5. Advantages of mobile devices

It’s not all about a limited user experience when comparing a mobile device to a PC, however. Modern mobile devices offer several advantages and features that desktop computers lack.

A mobile device is a completely personal item that the user carries on his or her person. So, for example, alerting the user about something while the device is not being used is a much more viable option than with a PC. And often, mobile devices have a lot of built-in equipment that isn’t commonly present on a PC, like a camera, a microphone, or a touchscreen.

6. Other

Even though processing power, memory, and storage space have taken huge leaps in mobile devices in recent years, PCs will always be able to pack more punch, simply because of sheer size. Mobile applications should be optimized to use as little hardware resources as possible. Wasting resources will lead to slower performance, and slower performance will lead to user frustration.

Power management is an important part of designing mobile applications. There is only so much battery power to toss around, and applications should preserve it as best they can. To read about Power Management, go to the Forum Nokia page.

Finally, a desktop PC is often used for hours at a time, whereas a mobile device is usually used for short tasks — it’s something you grab from your pocket when needed. This puts extra pressure on designers to create simple and quick interfaces.

Rate This