March 22, 2011 at 11:26 AM ET

Oh Lendle, you ended before you ever really got started!
Not even two months after Amazon introduced its Kindle users to Lendle, an e-book swapping service between Kindle-using friends and strangers, it has effectively pulled the plug on the third-party app.
A visit to the Lendle site now yields this sad message: "Amazon has revoked Lendle’s API access. Unfortunately, Lendle is unavailable indefinitely. We will do everything we can to restore service soon."
UPDATE: BookLending.com remains live.
Lendle co-founder Jeff Croft wrote about Amazon's decision to revoke API access to the app. Application Programming Interface is used to get data about books — things like titles, authors, cover images, etc.
Lendle relies heavily on Amazon’s api, so this effectively shut the site down. The letter we received from Amazon states that the reason our api and Amazon Associates accounts have been revoked is that Lendle does not "serve the principal purpose of driving sales of products and services on the Amazon site."
We take issue with this, as Lendle was built from the ground up to ensure that it would be beneficial to authors, publishers, and Amazon. Our site requires that you be willing to lend books before you can borrow them. We even went so far as to allow users to sync their Lendle accounts with their Kindle accounts, so that we could ensure anyone who borrows books on Lendle has previously purchased lendable books from Amazon. Our philosophy is: You can’t borrow if you don’t lend, and you can’t lend if you don’t buy.
The entire system we built is centered around the idea of encouraging people to buy books.
Croft writes about how blind-sided he and his company were by the news, and also revealed that the service was not singled out.
Our initial reaction was one of pure surprise. I work out of my home office just blocks from Amazon headquarters in Seattle, and am very involved in the tech community here in town. As such, I know many people at Amazon, and everything I’d heard was that most inside Amazon were big fans of Lendle — even up to higher-ranking managers.
We’re not sure why this action comes now. We’ve been operating for a month and a half now, with no complaints from Amazon. We didn’t make any significant changes to the site over the past couple of weeks that would have resulted in any kind of change in our compliance with Amazon’s terms. We do know that we’re not the only eBook lending site who had their api access revoked today, so we can only speculate that it wasn’t anything about Lendle specifically that caused Amazon to act today, but rather something a bit bigger than us. We know publishers have been skittish about lending, and aren’t yet seeing how much value it brings them, so we might speculate Amazon was acting on pressure from them. But really, we don’t know. We can only speculate.
As can we, although we have contacted Amazon so they can elaborate more on this.
Lendle's Twitter page has been abuzz with the commotion, frustration from the company and its users, in equal parts.
From user @mattash: "It's official, @amazon takes home the trophy for 'dumbest business move of the day' for shutting down @lendleapp."
Amazon, take heed, looks like some people actually bought more books because of apps like this.
From @amberh: "@lendleapp Sorry to hear it. I actually bought a ton more books because of you than I did before."
Croft added this response about the company's next steps, via email to us this morning:
We certainly could build a lending site without using Amazon's API — and we might, if we're unable to get our access restored. It would probably rely on user-generated data (for example, asking a user to type in the title of their book), and it would take us a bit of time to rebuild our site to work that way, but it's definitely possible. Amazon API access is not necessary for e-book lending sites, but it does make life for us a bit easier.
We've yet to hear anything from Amazon. As for next steps, we need a bit of time to regroup and figure that out. Right now, we're focused on all the press coverage, and on doing anything we can do get our API access back. If it looks like that's not going to happen, we'll look to rebuild without it, so we can continue to serve our amazing community of book-lovers.
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