About

Android is Google's software stack for mobile devices, developed by Google and the Open Handset Alliance. For non-reverse engineering questions, see the Android Enthusiasts Stack Exchange site.

From Wikipedia:

Android is a Linux-based operating system designed primarily for touchscreen mobile devices such as smartphones and tablet computers. Initially developed by Android, Inc., which Google backed financially and later bought in 2005, Android was unveiled in 2007 along with the founding of the Open Handset Alliance: a consortium of hardware, software, and telecommunication companies devoted to advancing open standards for mobile devices. The first Android-powered phone was sold in October 2008.

Android is open source and Google releases the code under the Apache License. This open source code and permissive licensing allows the software to be freely modified and distributed by device manufacturers, wireless carriers and enthusiast developers. Additionally, Android has a large community of developers writing applications ("apps") that extend the functionality of devices, written primarily in a customized version of the Java programming language. In October 2012, there were approximately 700,000 apps available for Android, and the estimated number of applications downloaded from Google Play, Android's primary app store, was 25 billion.

Android Versions

• 1.0 Astro (specified as BASE by Google)
• 1.1 Bender (specified as BASE_1_1 by Google)
• 1.5 Cupcake
• 1.6 Donut
• 2.0/2.1 Eclair
• 2.2 Froyo
• 2.3 Gingerbread
• 3.0/3.1/3.2 Honeycomb
• 4.0 Ice Cream Sandwich
• 4.1/4.2 Jelly Bean

Official API Documentation

• Android 2.3.3 Gingerbread
• Android 2.3.4 Gingerbread
• Android 3.0 Honeycomb
• Android 3.1 Honeycomb
• Android 3.2 Honeycomb
• Android 4.0 Ice Cream Sandwich
• Android 4.0.3 Ice Cream Sandwich
• Android 4.1 Jelly Bean
• Android 4.2 Jelly Bean

Applications

• Google Play

Source code and Building

• Source Code
• Source Mirrors
• Building and Running
• Building for devices
• Building kernel

Developers

• Android Developers
  Contains the SDK downloads, documentation, class reference and tutorials. Start here.

• Android Developers Blog
  Google's blog for Android developers, discussing technical topics as well as those relating to Google Play (formerly Android Market).

• Official Android Blog
  News and notes from the Android team

• +Android Developers on Google+
  News and announcements for developers from the Android team at Google. Also a venue for discussion of recent news and announcements.

• Android Design Guidelines
  A collection of UI guidelines for Android. Mainly focused on design patterns and navigation.

• @AndroidDev on Twitter
  News and announcements for developers from the Android team at Google.

• Android Developers Google Group
  Alternative developer discussion forum for Android.

• Android Open Source Project (also known as AOSP)
  Contains all necessary information about the Android source code.

• Android page on Wikipedia
  Detailed information about the Android OS.

• Android.com
  General information about the Android OS.

• Google I/O 2010 developer conference
  Contains detailed videos and slides by Android product engineers

• Google I/O 2011 developer conference
  Contains videos and slides by Android product engineers

• Google I/O 2012 developer conference
  Contains videos and slides by Android product engineers. (June 27-29 2012)

• [Google I/O 2013 developer conference][77]
  Site that will contain videos and slides by Android product engineers. Full conference can be watch on a live stream here. (May 15-17 2013)

• Google Maps API
  The Google Maps API port for Android, which provides a lot of information on how to use the Maps API on Android (which can not be found on the Android Developer site)

• Android Developer Channel @ Youtube
  Android Developer Channel. This is the home for videos containing demos, tutorials, and anything else related to Android, the first complete, open, and free mobile platform.

• Google I/O - Android sessions @ Youtube

• Android Tools Project Site
  On this site you will find information about the Developer Tools for Android (ddms, hierarchyviewer, lint) and various tips & how-to documents.

For non-developer questions, see the Android Enthusiasts Stack Exchange site.

Free Android Programming Books

• Building Android Apps with HTML, CSS, and JavaScript
• Learning Android

Android Development Book Recommendations

• Hello, Android by Ed Burnette

• Beginning Android Application Development by Wei-Meng Lee

• Android Apps for Absolute Beginners by Wallace Jackson

• The Busy Coder's Guide to Android Development by Mark Murphy

• Professional Android 4 Application Development by Reto Meier

• Android Wireless Application Development by Shane Conder & Lauren Darcy

• Pro Android Media: Developing Graphics, Music, Video, and Rich Media Apps for Smartphones and Tablets by Shawn Van Every

• The Android Developer's Cookbook: Building Applications with the Android SDK by James Steele & Nelson To

• Android Application Testing Guide by Diego Torres Milano

• Beginning Android 3 by Mark L. Murphy

• Programming Android by Zigurd Mednieks

• Android User Interface Development: Beginner's Guide by Jason Morris

• Learning Android by Marko Gargenta

• Embedded Programming with Android: Bringing Up an Android System from Scratch by Roger Ye