Kindle Unlimited

The Kindle Store is an online e-book e-commerce store operated by Amazon.com as part of its retail website and can be accessed from any Amazon Kindle, Fire tablet or Kindle mobile app. At the launch of the Kindle in November 2007, the store had more than 88,000 digital titles available. This number increased to more than 275,000 by late 2008, and exceeded 765,000 by August 2011. In July 2014, there were over 2.7 million titles available at the US store and as of April 2017 there are over 6.9 million titles available in the U.S. Content from the store is purchased online and downloaded using either Wi-Fi or Amazon's 3G Whispernet to the user's device.

In late 2007, new releases and New York Times best sellers were being offered for approximately $11 at the store, with first chapters of many books offered as free samples. Many titles, including some classics, are offered free of charge or at a low price, which has been stated to relate to the cost of adapting the book to the Kindle format. Magazines, newspapers and blogs via RSS are provided for a monthly subscription fee or during a free trial period. Newspaper subscriptions cost from $1.99 to $27.99 per month; magazines charge between $1.25 and $10.99 per month, and blogs charge from $0.99 to $1.99 per month. Amazon e-book sales overtook print for one day for the first time on Christmas Day 2009. International users may pay different prices for e-books depending on the country listed as their home address.

In February 2017, the Association of American Publishers released data that shows the U.S. adult e-book market declined 16.9% in the first nine months of 2016 over the same time in 2015. This decline is partly due to widespread e-book price increases, known as agency pricing, by major publishers that Amazon had recently allowed that brought the average e-book price from $6 to nearly $10.

As a member of Amazon Prime, access to the "Kindle Owners' Lending Library" is a perk that allows Kindle-owning members to borrow one e-book, choosing from over 600,000 titles as of July 2014, per calendar month from the Kindle Store.

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Wikipedia