Should you buy a tablet if you already have a smartphone and a laptop?

When the age of the modern tablet was ushered in just over a year ago with the introduction of Apple's iPad, tablets were called a "third class" of personal gadget to complement the laptop computer and the smartphone. The implication was that a tablet will be just as essential as those other devices have become — but is that really the case? Do tablets do anything you can't already do if you already have a laptop or a smartphone? Let's go over the facts to find the answer.

A unique angle?
Does a tablet do anything a laptop or smartphone can't do? There are plenty of things laptops do that smartphones can't, such as word processing, software and web development, tasks that require a ton of multitasking, and anything that demands a lot of processing power, a physical keyboard, or a large screen. Likewise, smartphones offer functionality your laptop will never offer — GPS directions when walking the streets of New York, entertainment on the train, and the ability to receive emails at a bar with no wifi.

Tablets are another story. There's not much basic functionality they can offer that's not offered by either smartphones or laptops. Tablets can give you GPS maps on the go, a full-featured web browser that's comfortable to use, and if you're accustomed to touchscreens, they can even handle word processing or photo editing.

If the $500-$1,000 cost of a tablet is only justified to you by new abilities and functionalities, you probably won't want to buy one. Other than a very strong battery life and the ability to surf the web on a large screen from anywhere — both of which are absent from most but not all laptops — there's nothing new here.

The performance advantage
Does a tablet do anything better than a smartphone? The answer to this question is a strong "yes." Even though a tablet like the Samsung Galaxy Tab doesn't do anything you can't do with either a smartphone or a laptop, it does so many things so much better than either of those devices.

Take GPS maps as an example. You can take your iPhone or Android phone with you on a trip and use it as a GPS navigation device, but you'll be squinting to see the maps. The large screen on the iPad makes apps like Google Maps that much more powerful. The same goes for anything with a strong visual element, like movies and games.

Even productivity apps are better on a tablet — more screen space means more real estate for options and features. That doesn't give a tablet an edge over a laptop, of course; laptops usually have even more real estate to work with.

Tablets vs. laptops
Does a tablet do anything better than a laptop? Surfing the web is better on a tablet. This doesn't make a lot of sense, since most websites are designed with laptops and desktops in mind, but it's true.

The physical form of a tablet is more comfortable to hold and interact with in almost every environment, and we can't say enough in favor of the multi-touch interface used by most tablets. It's that interface that sets tablets apart from laptops or desktops, in most cases. It's more powerful, making a mouse or a trackpad seem like a limiting relic of the past. Touching is more intuitive anyway, and a mouse only gives you one virtual finger with which to interact with the digital world; a tablet gives you 2, 3, or even 5.

Laptops are better at multitasking than tablets are, but focusing entirely on one application or task has its advantages, especially for creative types. Sure, multi-touch trackpads are becoming more common on laptops, but since they're not integrated with the screen, they're used only for gestures. That's nice, but a multi-touch tablet lets you interact with the content directly.

We've already noted that tablets have better battery life. Between that, their always-on internet (on 3G models, anyway), and their comfort of use on the sofa, in bed, or on the bus, it's clear that tablets are more fun to use for light computing tasks.

Should you buy a tablet?
Tablets won't add anything new to your life that you don't already get with your smartphone and laptop. If you can afford one, though, it will make your life a little more pleasant. They're more fun and powerful than smartphones across the board, and they do light computing tasks like web surfing better than laptops.

However, do not buy a tablet to replace either of those devices; it only adds something as a third device. You can't really use a Galaxy Tab while walking down the street because it's too big for that. And there are many heavy computing tasks that a tablet cannot do, which means ditching your laptop or desktop altogether would be something you'd regret later.

For those who already own the other two types of gadgets, a tablet is a luxury, not a necessity. Like all luxuries, we'd all be lucky to have them, but don't make huge financial sacrifices to make it happen.

[Image credits: TAKA@P.P.R.S, David Precious]

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