With so many kinds of mobile devices available today, it's no wonder that so many of us are less location-dependent (for both work and for play) than ever before. Mobile computing has come a long way, from the first laptop (perhaps as early as 1979) to the popularization of PDAs in the 1990s, to today's proliferation of smartphones, tablets, and pocket-sized mini computers. Here's what you need to know about the types of mobile devices that can help you get things done, wherever you are.
Laptops are of course the de facto portable computing device, since they are designed to do everything a desktop PC can do, just from different locations. The smallest and most portable notebooks, ultraportables, weigh under 3 pounds (or under 5 pounds, depending on who you ask) and have screen sizes 13" or under. While laptops have the most computing power of the mobile devices listed here and they can be very travel-friendly, they are actually the least portable of your mobile device options; many people are even starting to replace (or supplement) using regular laptops with smaller, more mobile devices. If you're in the market for an ultraportable, though, About's Guide to PC Hardware/Reviews has a selection of ultraportable laptops for you.
For some, even ultraportable laptops are too big. Netbooks, also referred to as subnotebooks, have a more compact form factor, with typically 10" screen sizes (though the first mass market netbook, the ASUS Eee PC had a 7" screen) and can weigh as little as 2 pounds. Netbooks are great because they're inexpensive, usually have long battery lives, and can do the most common (least processor-intensive) tasks most of us use our computers for, like surfing the Web, checking email, and using office productivity programs. They trade these benefits, however, for less robust performance. Using your netbook for work is possible, however, depending on your tasks.
The tablet, as a category of mobile computing devices, is less dependent on size or weight than on input -- they are computing devices that take input from a stylus and/or touchscreen (convertible tablets also offer a keyboard). Early tablet PCs championed by Microsoft used pen-based computing and ran a tablet-customized version of Windows XP (Windows Tablet PC Edition). More recently, especially after Apple's introduction of the iPad, tablets are moving away from running the same operating systems as desktop and laptop PCs, running instead mobile OSes like iOS and Android. As a result, those kinds of tablets may not run traditional desktop software, though they excel at cloud computing and offer a wealth of mobile apps. About's Guide to Portable Electronics has a nice Slate Tablet Roundup (I'm still wondering whether the iPad works for work).
Ultra-mobile PCs (UMPCs)
For traditional computing in the smallest package, ultra-mobile PCs (UMPCs) may be the answer. UMPCs are mini computers or, to be more precise, mini tablets (with touchscreen/stylus/keyboard input options). With displays 7" and under and weighing less than 2 pounds, UMPCs are true pocketable devices and offer traditional or full-fledged operating systems like Windows XP, Vista, and Linux (some UMPCs, though, run Windows CE and other specialized operating systems). UMPCs offer broader traditional or general-purpose application support than smartphones, and a much smaller form factor than laptops or netbooks. They also have less battery life and smaller screen real estate, however, and demand premium prices due to their small size and lower market demand. View a selection of the best UMPCs/MIDs based on hardware features and innovation.
Mobile Internet Devices (MIDs)
Mobile Internet Devices are often even smaller than UMPCs, with displays around 5". Designed specifically as "Internet in your pocket" and multimedia devices, MIDs usually don't have keyboards, but some of their advantages are near instant-on features, lower prices than UMPCs, and low power usage. They're best for Internet surfing and media consumption rather than traditional computing -- in other words, they won't replace your notebook. More: definition and examples of MIDs.
Smartphones, with their combination of Internet and wi-fi access as well as cellular communication capabilities, are perhaps the devices driving mobility today, for both professional and consumer purposes. iPhones and Android smartphones in particular are showing rapid growth, soon to surpass feature phones. With smaller screen sizes than MIDs and UMPCs, however, and many smartphones lacking hardware keyboards, working off a smartphone for extended periods of time can be limited. They are great communication devices, however, and for Internet surfing on the go; many business mobile apps also enable "anytime, anywhere" productivity.
Lastly, there's the venerable PDA. Though PDAs like the Dell Axim and HP iPAQ are going out of favor, since smartphones can do what PDAs do plus add telephony and data, PDA users still abound and using a PDA has some advantages over smartphones. Many smartphones require, for example, a monthly data plan, whereas you can use a PDA at a wi-fi hotspot for free data connectivity. There's also a lot of business-oriented PDA software still available, since the earliest PDA adopters were business users. The downside, however, is that PDA development has come to a halt, and the demise of the standalone PDA may just be a matter of time. As the earliest type of pocket-sized mobile computing device, though, PDAs have earned their place in the mobile device hall of fame.