The Android NDK is a companion tool to the Android SDK that lets you build performance-critical portions of your apps in native code. It provides headers and libraries that allow you to build activities, handle user input, use hardware sensors, access application resources, and more, when programming in C or C++. If you write native code, your applications are still packaged into an .apk file and they still run inside of a virtual machine on the device. The fundamental Android application model does not change.

Using native code does not result in an automatic performance increase, but always increases application complexity. If you have not run into any limitations using the Android framework APIs, you probably do not need the NDK. Read What is the NDK? for more information about what the NDK offers and whether it will be useful to you.

The NDK is designed for use only in conjunction with the Android SDK. If you have not already installed and setup the Android SDK, please do so before downloading the NDK.

The sections below provide information and notes about successive releases of the NDK, as denoted by revision number.

Android NDK, Revision 6b (August 2011)
This release of the NDK does not include any new features compared to r6. The r6b release addresses the following issues in the r6 release:

Important bug fixes
Fixed the build when APP_ABI="armeabi x86" is used for multi-architecture builds.
Fixed the location of prebuilt STLport binaries in the NDK release package. A bug in the packaging script placed them in the wrong location.
Fixed atexit() usage in shared libraries with the x86standalone toolchain.
Fixed make-standalone-toolchain.sh --arch=x86. It used to fail to copy the proper GNU libstdc++ binaries to the right location.
Fixed the standalone toolchain linker warnings about missing the definition and size for the __dso_handle symbol (ARM only).
Fixed the inclusion order of $(SYSROOT)/usr/include for x86 builds. See the bug for more information.
Fixed the definitions of ptrdiff_t and size_t in x86-specific systems when they are used with the x86 standalone toolchain.