Fire OS

Fire OS is a fork of the Android mobile operating system produced by Amazon for its Kindle Fire range of tablets. Fire OS primarily centers around content consumption, with a customized interface and heavy ties to content available from Amazon's own storefronts and services.

While the Kindle Fire line has always used customized distributions of Android, particularly 2.3.3, API level 10 (Kindle Fire) and 4.0.3, API level 15 (Kindle Fire HD), Amazon only began referring to the distribution as Fire OS beginning with its third iteration of Kindle Fire tablets, which includes the Fire HD 2nd generation and Fire HDX models. Unlike previous Kindle Fire models, whose operating system is listed as being "based on" Android, their operating system is listed as being "Fire OS 3.0 (compatible with Android 4.2.2, API level 17)".

Features
Fire OS uses a customized user interface designed to prominently promote content available through Amazon services, such as Amazon Appstore, Amazon Instant Video, Amazon MP3, and Kindle Store. Its home screen features a carousel of recently accessed content and apps, with a "favorites shelf" of pinned apps directly below it. Sections are provided for different types of content, such as apps, games, music, audiobooks, and video among others. A search function allows users to search through their local content library or Amazon's stores. Similarly to Android, sliding from the top of the screen exposes quick settings and notifications. Fire OS also provides integration with Goodreads, Facebook, and Twitter. X-Ray is also integrated into its playback functions, allowing users to access supplemental information on what they are currently viewing. On the Kindle Fire HDX, an additional function called "Mayday" allows users to connect directly to a support agent for assistance via one-way video chat. Amazon claims that most Mayday calls would be answered within 15 seconds. The OS features a user system, along with Kindle FreeTime, a suite of parental controls which allow parents to set time limits for using certain types of content.

Fire OS devices are exclusively tied to Amazon's software and content ecosystems; they do not offer any access to Google Play or provide any of Google's proprietary apps or APIs, such as Google Maps or Google Cloud Messaging. In lieu of Google Maps, Fire OS offers Nokia's Here Maps with a clone of Google Maps API 1.0. As Fire OS is incompatible with Google's official Android compatibility standards, Fire OS devices cannot include Google's proprietary software or use the Android trademarks. As members of the Open Handset Alliance (which include the majority of Android OEMs) are contractually forbidden to produce Android devices based on forks of the OS, Kindle Fire tablets are manufactured by Quanta Computer, who is not an OHA member.

List of Fire OS devices

 * Kindle Fire
 * Kindle Fire (2nd generation)
 * Kindle Fire HD
 * Kindle Fire HD (2nd generation)
 * Kindle Fire HDX