If you're interested in the electronic book craze, but you don't yet own an e-book reading device, your options just got a lot more complicated. Not only are there a handful of great devices that use electrophoretic screens from Cambridge, MA-based E Ink, such as the Amazon (Nasdaq: AMZN) Kindle, the Barnes & Noble Nook, and the Sony Reader Daily Edition; now there's also the Apple (Nasdaq: AAPL) iPad, for which there are at least 400 book-related apps, notably Apple's own iBooks and a superb Kindle app from Amazon. What's a reader to do?

I could go on for screens and screens about the relative merits of the iPad and the E Ink devices -- and I will. But let me cut to the chase. It pains me a little to say it -- and it will certainly pain Amazon, Barnes & Noble, and Sony -- but if you haven't already bought a Kindle-style device, don't. You'd be far better off saving up your cash and buying an iPad, even though the low-end iPad, at $499, is almost twice as expensive as the Kindle and the Nook, which cost $259.

Why? Because the iPad offers not only the best e-book reading experience available, but can do thousands of other amazing things too. The Kindle, even if it does connect with Facebook and Twitter now, is just a Kindle.

Now, I'm still a devoted Kindle fan. And even though my own Kindle has probably been feeling neglected since I brought home my iPad on April 3, I want to make it clear that I don't think current Kindle owners should feel remorseful about their purchases. The Kindle has its advantages and may still be the better choice for some people.

But the simple fact is that the iPad really is almost as magical as Steve Jobs promised it would be, at least in my opinion. It accomplishes the main goal of any handheld e-book device -- breaking digital text free of its former imprisonment on the screens of desktop and laptop PCs and presenting it in a more portable, book-like form -- while performing quite a few other tricks in the bargain. I don't think the iPad and the other tablet devices coming behind it will completely kill off the E Ink devices, but it will severely limit their market.

I'm going to run through the list of areas where the iPad clearly outshines the Kindle, and then I'm going to talk about a couple of ways in which the Kindle still beats the iPad. I think that most of what I'm going to say about the Kindle applies to the other E Ink devices too, but I haven't spent as much time with the Sony or Barnes & Noble e-readers, so I won't make any strong claims about them. The bottom line is that Amazon should probably concentrate on marketing e-book content, because there's no way it can compete with Apple's hardware.

1. The Screen
No contest here. The iPad's screen is obviously larger than the Kindle's -- 45 square inches for Apple's gadget, compared to 17 square inches for Amazon's -- but it's also got a) color b) animation c) multi-touch. When you download Apple's iBooks app, you get a free copy of A.A. Milne's 1926 classic Winnie-the-Pooh, including Ernest H. Shepherd's original color illustrations, which is quite canny of Apple, because the book shows off the brilliant LCD screen (and is also sure to prompt the children of iPad owners to demand more e-books). Placed next to an iPad, the Kindle looks rather sad. It's just fine for monochrome graphics -- in fact, its electronic-ink screen has a higher effective resolution than the iPad's -- but let's face it, even the New York Times gave up on black-and-white back in the '90s.

If your platform has a color screen powered by a speedy graphics chip, that means you can enhance your e-books with video and animation (more on that below). And when you combine animation with a touchscreen, the reading interface itself can be brought to life. On a Kindle, you advance through a book by clicking a physical "next page" button. But on the iPad, you sweep your finger across the page, in a motion that's pretty much the same as turning the pages of a real book. In a bit of utterly useless but fun embellishment, iBooks even simulates a curling page as you drag your finger from right to left. All that's missing is the fluttery paper sound.

With a color screen, you can also do cool things like changing the background and text shades. (I particularly like the "sepia" setting on the Kindle iPad app.) I admit that I originally thought the iPad's big color screen wouldn't make much of a difference when it comes to relatively static content like text. I was wrong -- it's a game changer.

2. The Books
In the race to build a big catalog of e-books, Amazon still has a big lead on Apple. There are almost half a million titles available for the Kindle, compared to a reported 60,000 for iBooks at launch. But here's the thing: The iPad is also a Kindle. In a remarkable act of self-cannibalization -- or maybe it's just a case of if-you-can't-beat-em-join-em -- Amazon has built a free Kindle app for the iPad that lets iPad owners read any Kindle edition that Amazon sells.

On the iPad, you can shop for titles at Amazon's website using the device's built-in Safari browser. All the books you buy go into your Kindle archive, from whence they can be downloaded to any Kindle-ready device, meaning an iPhone, an iPad, or an actual Kindle. The "WhisperSync" feature built into the Kindle app means you can switch between these devices, and always pick up right where you left off.

Because I have so many Kindle editions stacking up that I haven't finished reading yet, I haven't bought any iBooks titles so far -- and I don't really plan to. Why would I, when Amazon is giving me the best of both worlds? In fact, I think I'll probably keep buying most or all of my e-books from Amazon, and reading them on whatever device is most handy.

I have a philosophical as well as a practical reason for this policy. As I explained in a February column, Apple is using an "agency" model for iBooks under which publishers are, in theory, free to slap higher prices on iBooks editions than Amazon long imposed for Kindle editions. In practice, publishers seem to be charging the same prices so far on both platforms: for example, both the Kindle version and the iBooks version of A River in the Sky, a New York Times bestseller by Elizabeth Peters, go for $12.99, and I haven't been able to find any examples of big price differences this week. But as articles by Ken Auletta and other analysts have detailed, publishers eager to get around Amazon's former $9.99 e-book price ceiling have been gleeful about the Apple agency model, and may simply be waiting for the right moment to jack up the prices on iBooks titles. My own opinion is that e-books shouldn't cost much more than $9.99, so I'm avoiding iBooks on principle until this whole thing settles out.

3. The Other Apps
If you don't like Apple's iBooks app, you can get e-books for your iPad from Lexcycle or Kobo or Amazon or dozens of other distributors who have published iPad apps. That's because the iPad is a multipurpose device -- a literal blank slate, built specifically to support a huge range of software for learning, entertainment, and productivity.

The Kindle, on the other hand, is a single-purpose device, built specifically for reading e-books -- and only e-books purchased from Amazon. If you don't like Amazon, there isn't much reason to own a Kindle. Despite the drone of criticism from the digerati over the supposedly closed nature of the iPad/iPhone ecosystem, and despite Amazon's plans for allowing third-party apps on the Kindle, its hardware is far more closed and less versatile than Apple's.

A case in point: Vook. A couple of months ago I reviewed two iPhone apps from the Emeryville, CA-based startup -- a Sherlock Holmes double-header enhanced with clips filmed in Holmes's native London, and Gary Vaynerchuck's Crush It!, a motivational business title spiced up with the hyper-extroverted wine entrepreneur's videos. Now Vook has 32 titles for the iPad, including an amazing one called Best of Times; it's a collection of 14 experimental videos created by Brooklyn filmmaker and New York Times blogger Jeff Scher, framed as an e-book, with commentary by the filmmaker about each video. Scher's animations are amazing. I'm not sure if "vooks" are the future of books -- but there's no question that the iPad gives authors and publishers much more room to experiment than the Kindle. (That's one of the arguments I make in an essay published in the May/June issue of Technology Review.)

What it really comes down to is this: If you're already thinking about spending $259 just to read e-books, why not spend an additional $240 so that you can watch movies, listen to music, read comic books, play games, surf the Web, manage your e-mail, edit documents, browse maps, play a synthesizer, create digital paintings, search for recipes, make Skype calls, and, of course, keep up with your friends on Twitter and Facebook?

Okay, I promised I'd say something about the Kindle's advantages over the iPad. It's a shorter list.

1. Weight and handling. The iPad weighs a pound and a half; the Kindle weighs one-third as much. Try using an iPad for a while and then go back to a Kindle: the Amazon device feels amazingly light and airy. If you like to hold your reading device in one hand while you read, the Kindle is for you. The iPad, by contrast, requires a perch, such as your chest or lap or an airline tray table.

2. Battery life. The iPad's batteries last a surprisingly long time, at least compared to MacBooks or iPhones. I've gone three days without having to plug mine in. But the Kindle still wins out here. If you turn off the wireless card on your Kindle, it can go for weeks on a single charge. (That said, if you just want something to read on a cross-country plane flight, the iPad's batteries are more than sufficient.)

3. Periodicals. You can subscribe to hundreds of magazines and newspapers on the Kindle. New issues are delivered wirelessly and automatically (assuming you haven't turned off the wireless to save battery power). In a major disappointment, the Kindle iPad and iPhone apps can only retrieve your archived books, not your periodicals -- so all my copies of the New Yorker and the Atlantic are stranded on my Kindle. And there's no such thing as an iBooks magazine or newspaper: Apple is leaving it to the individual publishers to create their own iPad apps. So far there isn't much of a selection, and the price per issue is far higher than what you'd pay for a Kindle version.

4. The "hard core reader" issue. In a TechFlash article back in January, Scott Jacobson, a former Amazon executive, gave five reasons why the iPad is not a Kindle killer. Jacobson's Reason No. 1 was that the Kindle already works perfectly well for serious readers who just want to immerse themselves in a good book -- in other words, people who are more interested in Jane Austen's Emma than in Alicia Silverstone in "Clueless." "There is a segment of the market…that will prefer a less-expensive device that does one thing really well…And that segment will continue to choose Kindle," Jacobson wrote. I think this is a good point -- and as I think I've made clear, I'm not about to throw out my Kindle. I just don't think this segment is large enough to support a booming hardware business.

Interestingly, Jacobson's reason No. 5 was "Amazon can't afford to lose." That may be a true sentiment -- but it's not exactly a concrete defense of the Kindle. If Amazon really wants to stay in the hardware game, it's going to have to come up with something stunning. But what's the point of trying to beat Steve Jobs at his own game?

My own guess is that Bezos & Co. see digital books, not the hardware they appear on, as the real prize. At some point a few years ago they decided they had to build a kick-ass e-book reading device simply to demonstrate that there was a market for books delivered electronically. They've now proven that point -- Jobs admitted as much in his speech introducing the iPad, when he said "Amazon's done a great job of pioneering this functionality with the Kindle. We're going to stand on their shoulders and go a little further."

The cool thing about the iPad, which Amazon seems to have recognized already by building its own iPad app, is that it's a great platform for Kindle books. And now that Amazon has jump-started the e-book market, it may be that it can afford to lose, at least on the hardware front, as long as it can still sell e-books to owners of iPads and other gadgets. In fact, maybe Amazon should be happy to let Apple -- which has been doing this a lot longer, after all -- handle the hardcore engineering that goes into making hardware magical.

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Wade Roush is Xconomy's chief correspondent. He does not own shares of any company mentioned. You can e-mail him at [email protected] or follow him on Twitter at twitter.com/wroush.

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