Ranked in these QuestionsQuestion Ranking
Pro Good offline capabilities
Pro Free and open source
Eclipse is a free and open source software, it's released under the Eclipse Public license.
Pro Java programming language and XML editors
Has full support for both Java and XML.
Pro Large selection of plugins
Eclipse has a large and active community, which has resulted in a wide variety of plugins.
Pro Graphical interface
ADT provides GUI access to many of the command line SDK.
Pro Highly customizable
Thanks to the large variety of plugins and various configuration options, Eclipse is very customizable.
Pro Good font rendering
Because Eclipse is based on SWT, it uses the native font rendering and thus looks better than other IDEs on some Linux systems, where the Java font rendering is not optimal.
Con Plugins can be unstable
Though there are plenty of plugins to choose from, they aren't always reliable. Some aren't maintained, bug fixes can be slow, and you may need to download plugins from multiple sources.
Con May lose support in the future
Google recommends moving away from Eclipse for Android Development, plugins and features are adopted much later from Eclipse than from Android Studio or IntelliJ IDEA and in the future the ADT plugin may be abandoned altogether.