Android SDK is a reliable software development kit issued by Google in
order to provide developers with a comprehensive set of tools for
building Android applications. If used properly, the SDK, together
with Eclipse (the officially supported IDE) and JDK (Java Development
Kit) is able to deliver state-of-the-art software for Android devices.
The package bundles a decent set of libraries and development tools to
assist programmers in building and testing applications. However, a
more complete solution, bent on helping new or less experienced
Android developers, is the ADT Bundle. The latter comprehends a more
generous collection of utilities, including Eclipse, Android Platform
Tools and the latest Android system image.
On the other hand, Android SDK comes in a lighter package and assumes
that developers already have the Eclipse IDE installed, as well as JDK
and the Android Development Tools plugin (not compulsory, although
recommended). In other words, the SDK includes only the basic
utilities for Android app development.
Initially, the package doesn't contain an Android platform or
third-party components. In order to accommodate these on the system,
you are required to start the SDK Manager and install at least one
platform together with its adjacent tools.
The reason that explains this kind of procedure is simple: platform
utilities are updated periodically to support new features and
repacking the SDK each time would cost time and efforts, not to
mention the size of the final package. This is why Google adopted a
simpler method, which, of course, requires an Internet connection, but
has the advantage of keeping you up to date with the latest platform
features.
In addition, Android SDK supports older versions of the platform,
ranging from Android 1.1 to the latest release. As such, developers
may build applications for older devices and test their compatibility
with the latest platform.
All in all, the SDK is a great companion for Android developers.
Although aimed at experienced developers, beginners can make the most
of it as well, if proper research is made.