The Amazon Kindle line of e-readers have been incorporating 3G internet access since the very first model that came out in 2007. Whispernet internet access is provided by AT&T and gives owners the ability to browse the web, purchase eBooks and download content. The big point of confusion that e-reader owners have, is what are the limitations?
The Whispernet feature was co-designed with Qualcomm, and Kindle was the first device to include free nationwide 3G access to download books from the Amazon web store. The internet access is provided by AT&T and works in all coverage areas across the globe. The ability to surf the web has prompted many customers in China to bypass the Great Firewall by way of the AT&T tower in Taiwan.
Amazon does not really advertise the data caps that are involved when you pay the premium fee to access Whispernet. Â Originally, the Whispernet service had no limitations on the amount of data downloaded, but some users learned that they could hack their Kindles to turn them into wireless hotspots for other devices. The increased data consumption by these users has led AT&T to place limits on the system.
Whispernet now offers users 50MB of data per month, but once you hit that limit, Amazon blocks all content other than the Amazon store and Wikipedia over the 3G connection. Users who hit the limit can still browse over the Kindle’s built-in Wi-Fi connection, and organizations can continue to deliver content over their own wireless network.
There are no monthly fees for the 3G Whispernet access, but the Kindle service is different than the standard monthly rates you incur with the Fire line of tablets. The only way you would pay extra per month on the e-reader is if you opt into the Kindle Personal Documents Service. This a  is a free tool that allows you to send documents directly to supported Kindle devices and Kindle reading applications linked with your Amazon account. Documents can be sent from the Send-to-Kindle application or from an authorized e-mail address. Basically it is free if you connect it up to WIFI but costs  $.15 per megabyte domestic and $.99 per megabyte international.
Whispernet was one of the main contributing factors that propelled Kindle sales into the stratosphere. Customers found the process of buying books was super easy and intuitive. Instead of being tied down to a WIFI network, you can buy eBooks while on vacation, laying on the beach or traveling. Â Barnes and Noble tried emulating it with their first generation Nook e-reader, but gave up on it after incurring massive costs.
Michael Kozlowski is the editor-in-chief at Good e-Reader and has written about audiobooks and e-readers for the past fifteen years. Newspapers and websites such as the CBC, CNET, Engadget, Huffington Post and the New York Times have picked up his articles. He Lives in Vancouver, British Columbia, Canada.