Android is a mobile operating system initially created by Android Inc., and based on the open source Linux kernel. Linux, created in 1991 by Linus Torvalds, is still one of the most significant examples of open source software ever available.
Google acquired Android Inc., in 2005, and along with other members of the Open Handset Alliance, developed and released Android in 2007. The Android Open Source Project (AOSP) now maintains and expands the Android system. Figure 3-1 shows the Android logo.
Android includes an operating system, middleware, and some key applications. It is designed to be optimal for use in the mobile environment, and is flexible and upgradeable. The most recent versions at the time of this writing are Android 2.3 (called Gingerbread, released in fall 2010), and Android 3.0 (called Honeycomb, released at the beginning of 2011).
Android penetration on mobile devices is rapidly expanding. More information on Android is available at http://www.tbray.org/ongoing/When/201x/2010/11/14/What-Android-Is.
Early feedback on developing applications for Android was not very positive. The system was buggy, there was no bug tracking in place, and very little documentation was available. Nowadays, developing for this system has greatly improved. A public issue tracker is available and an active community has grown (see http://source.android.com/ and http://developer.android.com/index.html). The Android framework enables the reuse and replacement of components. As an AIR developer, you can read these forums to stay informed on system development and native functionality. An additional forum is also maintained on the Adobe site for specific questions regarding AIR for Android: http://forums.adobe.com/community/air/development/android.