Why doesn't Amazon's Kindle allow reading EPUB files?

By: (plus.google.com) +David Herron; Date: October 15, 2017

Tags: E-Books »»»» E-Readers »»»» EPUB »»»» Amazon Kindle

The EPUB3 format has been documented in the open since 2010, but Amazon hasn't seen fit to implement it on the Kindle. Instead, Amazon uses a proprietary version of the MOBI format. Since the Kindle is such a dominant force in electronic books, the whole e-Book market is being held back. As I pointed out the other day, e-Reader innovation hasn't stalled, the public is prevented from enjoying the advances which have occurred, because of Amazon's actions. Amazon doesn't say why they've done this.

The "Why" appears to be related to these two issues:

  • Lock-in: Meaning that Amazons goal is steering customers into using the Kindle Reader, and therefore keep buying books through the Kindle Marketplace. Many businesses follow this model - an airline rewards programs strongly encourages passengers to keep flying with that airline.
  • Pre-existing software: Amazon began work on the Kindle in the early 2000's, well before the EPUB format was invented. It means Amazon has a whole toolchain based on its MOBI-based e-Book format, and adopting EPUB would mean rewriting that toolchain.

The second problem is obviously an engineering challenge. Amazon could tell their software team to develop EPUB support. The easiest route might be incorporating one of the browser engines into the Kindle. The core of Google Chrome has been used many ways - such as the V8 JavaScript engine becoming the heart of Node.js, and the many applications built to the Chrome-based Electron framework, such as Microsoft's Visual Studio Code (that I'm using to write this posting).

Amazon is already able to directly import an EPUB file into the Kindle bookstore - I've done it several times using EPUB's I built with (akashacms.com) the EPUB Tools software I designed.

While the second problem is simply a solvable technical challenge, Amazon has two reasons for not solving that problem:

  1. Opportunity cost and the allocation of resources: Software engineering management's are always allocating their resources (hours of engineering time) to one project or another. Amazon has N engineers working on Kindle, giving them N*40 hours per week of engineering time with which to pursue their goals with the Kindle platform. If the engineers are directed to develop EPUB support, what other features will they NOT develop?
  2. Two kinds of Kindle: Amazon wouldn't be able to retrofit EPUB support into existing Kindles. Therefore, Amazon would have to deliver e-Books in their proprietary MOBI format to some Kindles, and in the EPUB format to other Kindles.

By adopting EPUB Amazon would a more powerful e-Book format that can deliver a more interesting/useful reading experience. With EPUB3, developed in 2010, e-Books can be implemented with most of the advanced features we enjoy on websites today. EPUB3 adopted most of the HTML5 and CSS goodness that revolutionized the Web a couple years ago. Amazon's customers could be even more delighted with Kindle books if they were capable of what EPUB3 potentially allows.

Doesn't that give Amazon an incentive to head in that direction?

Perhaps, or perhaps instead it makes Amazon steadfast in NOT adopting EPUB. That's because other e-Book marketplaces also sell books in the EPUB format. If the Kindle were able to directly view EPUB's, those other marketplaces could conceivably win more than Amazon would win.

While the technology is a solvable problem - even the Two kinds of Kindle problem is solvable - the business model issue is not so solvable.