Fourth generation: Kindle
Kindle
Amazon announced the fourth generation Kindle on September 28, 2011, offering both ad-supported and non-ad supported models, retailing for $79 and $109 respectively. Retaining the 6 inch e-ink display of the previous Kindle model as well as Amazon's experimental web-browsing capability (when within Wi-fi range), the fourth generation Kindle features a slightly smaller and lighter form factor[42] as well as five hard keys, a cursor pad, an on-screen rather than physical keyboard, a flash storage capacity of 2GB, and an estimated one month battery life.[43][44]Kindle Touch
Amazon announced a touchscreen version of the Kindle on September 28, 2011; available with Wi-Fi ($99 ad-supported, $139 no ads) or Wi-Fi/3G connectivity ($149 ad-supported, $189 no ads). Via 3G is enables to connect just to the Kindle Store, download books and periodicals, and access Wikipedia. Experimental web browsing (outside of Wikipedia) on Kindle Touch 3G is only available over Wi-Fi. [45]. The device uses the same 6-inch E-ink screen of the previous Kindle model, with the addition of an infrared touch-screen control.[42] Like its predecessor, the Kindle Touch has a capacity of 4 gigabytes and battery life estimated at two months.[46] The Kindle Touch began to ship on November 15, 2011.[47]Kindle Fire
Main article: Kindle Fire
Amazon announced an Android-based tablet with a color touch screen on September 28, 2011. It costs $199 and has a 7-inch IPS display. This is the first Kindle without an E Ink display. Unlike previously released Kindles, it has no 3G option. The Kindle Fire also has an unused light sensor but lacks a microphone, camera, and an SD card reader. It has 8GB of storage and a projected battery life of up to eight hours. [32]