Amazon, Lendle and the Danger of Using Open APIs

Lendle, an ebook-sharing service that allows users to find and trade Kindle books, sounds like a great idea except that it doesnt work anymore, because Amazon pulled the plug on the site by blocking access to the Amazon API. According to Lendle co-founder Jeff Croft, there was no warning from the online retailer, only a cryptically worded email. And so Lendle becomes the latest poster child for a simple maxim: Building your service on top of someone elses API, no matter how open it is supposed to be, is a very dangerous road.

No one knows the downside of this approach better than Bill Gross, the founder of UberMedia, which the veteran Silicon Valley entrepreneur has built into a kind of Twitter client rollup by acquiring services and apps such as UberTwitter and Echofon. Gross originally had a great idea for selling advertising around tweets as well, but then Twitter launched its own identical advertising platform. Earlier this year, after what Twitter said was bad behavior by some of UberMedias apps, the social-media platform shut down the companys access to the Twitter API.

In UberMedias case, the company made some changes to its apps, and Twitter turned the API tap back on. Its not clear whether Lendle will be able to modify the way its service works to make Amazon happy, however the online retailer has not made any statement about the action it has taken against the ebook-lending service other than to say that Lendle doesnt serve the principal purpose of driving s! ales of products and services on the Amazon site. Weve emailed Amazon and will update this post if there is any response.

Is Amazon planning its own lending service, or is it simply afraid that more borrowing of books equals less buying?The answers to those questions remain unclear until the company clarifies its reasoning (Lendle says users buy more books after borrowing them).

Twitter used to be the most obvious example of a company that was willing to let developers do pretty much whatever they wanted with the services data and that open approach arguably helped to create much of the networks value, including popular conventions such as the retweet, the @ mention and so on. But Twitter has been tightening the reins for some time now on what it allows, and its latest pronouncement made it clear that certain aspects of its business are simply off limits for third-party developers.

In some ways, thats a natural evolution for a company: to be open with its data when it is trying to grow, and then to shut down or restrict that as it tries to become a functioning business and make money. Amazon has long since passed that point, of course, and Lendle is only the latest to find out that what it thinks is a good service and what a company like Amazon thinks can be two very different things and whoever controls the API wins.

Post and thumbnail photos courtesy of Flickr user Will Clayton

Related content from GigaOM Pro (subscription reqd):