Sizing up Amazon's Kindle in its many forms

On Monday evening, Amazon announced that it would soon be offering a Kindle app for Android. This shouldn't have come as a surprise to anyone considering the company already had software applications for the PC, Mac, Apple's iPhone and iPad, and BlackBerry phones. But it is worth delving into how the Kindle apps on these platforms differ, if at all, and which one has the best non-Kindle Kindle experience.

Amazon has not been resting on its laurels when it comes to the Kindle as a platform. While the Kindle hardware itself is only in its second generation, the strength of Amazon's strategy is in getting its digital bookstore into the hands of as many users and on as many platforms as possible. The end goal, you see, is that everyone buys their books from Amazon, even if they're not willing to invest in the Kindle hardware itself.

What becomes clear, though, the closer you look, is that the Kindle software Amazon provides for third-party hardware is universally less full-featured than what one can do on a Kindle proper. Is that by design? Certainly. We'll delve into that a little later on. In the meantime, let's start by taking a look at Amazon's various kindle apps by order of release.

The platforms

Apple iPhone/iPod Touch (March 2009)
The iPhone and iPod Touch Kindle application (download) was the first of Amazon's efforts to offer Kindle users a way to read their books on something other than a Kindle device. Amazon released it about a year and a half after the launch of the first Kindle hardware, and just a month after the launch of the second-generation device.

At launch it wasn't the first e-book-reading software for the iPhone platform, nor was it the best. Competitor Stanza, which Amazon ended up acquiring just a month later, offered far more features as a reader, though it was missing a first-party sales library and a way to sync reading sessions, and titles between devices.

For iPhone and Kindle users alike, the release of this software was a big deal, since they could get all their purchased books synced to their iPhone or iPod without having to pay extra. And not so secretly, Amazon was hoping the app would act something like a gateway drug to get users to buy the Kindle hardware in order to get a fuller reading experience.

One problem that was apparent at the release of the iPhone app, and that still exists today, is that you cannot actually purchase books from within the app. Instead, it kicks you out to Safari to browse and purchase. As we go on you'll find this is a bit of a pattern.

Windows (November 2009)
Amazon released the PC version (download) of its Kindle reader software to users in early November 2009. Like the iPhone iteration, it did something the Kindle hardware itself could not do, which was display illustrations and digital publications in full color. It also had the rather obvious benefit of being able to use whatever peripherals were attached to your computer, like the mouse and keyboard to turn pages and adjust various options.

However, the real reason to use the PC software was its potential for use on tablet PCs, which Microsoft highlighted a month prior to the software's release at the Windows 7 launch party. Windows 7 users could use pinch gestures to change the zoom level of the page, as well as use a swiping motion to turn pages--all things that regular Kindle users could not do on the Kindle hardware.

BlackBerry (February 2010)

The Kindle software app came to BlackBerry (download) users just three months ago (to the day) and works on seven of Research In Motion's phones. Like the other apps, it syncs up with whatever purchases you've made, as well as bookmarks, notes, and your progress, though it doesn't let users create new annotations.

Because of the variety between the smaller-style screen models and the large, touch-screen models, the two reading experiences can differ drastically. For obvious reasons, users with larger screens can see more text, and those words comes across more clearly. Even so, small screen reading can be just as enjoyable for those with the smaller screens, and Amazon has coded in a simple system where you can use the BlackBerry's space bar to turn the page.

Mac (March 2010)
Amazon released the Mac version (download) of its desktop Kindle app to Mac users back in March, and it was met with lukewarm enthusiasm. Despite being released four months after its PC cousin, the Mac version didn't offer anything PC users weren't already getting. And just like the PC version, it was missing a way for users to create annotations or highlight passages, leaving that functionality exclusive to people with the Kindle hardware.

The Mac version also drew criticism for not taking advantage of some of Apple's gestures, such as pinching to zoom--something the PC version was able to do for Windows 7 users with touch screens, or multitouch trackpads. Also, users with PowerPC processors and/or the Tiger (OS X 10.4) operating system were shut out of being able to install the software.

Limitations and criticisms aside, Amazon said up front that the software was beta, and like all its other Kindle apps, offered it free of charge.

Apple iPad (March 2010)
The iPad version (download) of the Kindle software is the most interesting on this list because, unlike any of the others, the iPad is easily the Kindle's biggest threat.

The Kindle app on the iPad is very much like a grown-up version of its touch-friendly sibling on the iPhone and iPod Touch, except bigger (see the difference in the screenshot below). The amount of text you can see on the screen rivals that of the Kindle hardware itself, though comes in full color with three page themes and a dimmer toggle that can tone down the intensity of a white screen without actually lowering the device's brightness.

Apple does not yet ship the iPad with its iBooks storefront and reader application, but offers it as a free download (complete with a reminder) the first time iPad users head to the iPad's App Store. And unlike what Amazon has done with any of its Kindle apps, Apple actually combined the storefront and the reader in one--just like Amazon offers on its own Kindle hardware.

For more on how the two apps differ, read my colleague Rafe Needleman's take.

Android (this summer)

So what will Android's story be? From the looks of things, it's going to be the same as most of the other apps on this list. It will sync up whatever page you were on if you were reading the same book on another device, as well as giving users both a portrait and landscape mode.

It also appears as if the storefront aspect of making purchases will continue to exist within a Web browser, instead of an in-app directory.

These are all minor details, though. Where things get interesting is if Android gets a tablet-flavored shot in the arm at Google I/O this week. That would signal that there could soon be sibling apps on Google's burgeoning platform just like there are for the iPhone and iPad. But more importantly, it would mean yet another device that would replace some of the functionality--and need--for Amazon's own Kindle hardware.

Which one's the best?

The answer here should be quite obvious: whatever you've got with you. These applications were all designed to be a companion to the Kindle hardware as much as they exist to add an extra sense of value on top of whatever digital content is purchased.

If I had to pick personally, I'd go with the iPad version since it's around the same size as Amazon's Kindle hardware. But that doesn't mean I'd pick it over the Kindle hardware if it was something I was going to use every day. The Kindle's e-ink display is far easier on your eyes, it works well in sunlight, and you get free 3G for the lifetime of the product to browse and download titles. These are three big things the Kindle hardware has on all these software apps and the hardware they run on (go here for a full list).

The bigger issue at hand is that Amazon inherently limits the features it includes in these apps. This is because it's in Amazon's best interests to get you to buy its own device, where the Kindle store is the only way to go. Going forward, it will be interesting to see which features Amazon chooses to add to these apps, either from the Kindle itself, or its Stanza acquisition, in order to keep up with competitors. Or, in the case of devices like the iPad--where there is already an incumbent--whether Amazon chooses to make software that's even better.