Android Studio is the software built by Google themselves to be used for Android Development. As such, it's certain that support for it will never drop as long as Android apps are still being developed.
Studio is also the tool that Google recommends using for Android development and it's the IDE that gets updates related to Android first.
Because it's made by Google to be the tool to be used for Android Development, it's also very easy for Google to add great support for their services in the IDE and make it easier to integrate Google Services into Android applications built with Studio.
Android Studio uses Gradle as the official build tool for projects, moving away from the now outdated Apache Ant.
Gradle is a powerful build tool, especially for Android development with which it's very easy to do things that are otherwise impossible or very hard to do on other build systems, thing like: upgrading the build system without breaking the project itself or allowing you to separately define the development and production versions.
Since Android 2.0, Google have been focusing more and more on the IDE's speed, going so far as making it 2-2.5 times faster than older versions.
But the greatest feature when it comes to speed though is the new feature called "Instant Run". This is comparable to writing HTML, where you write the HTML and just refresh te page to see the changes. On mobile though, updating anything would take a lot of time for the system to rebuild.
Instant Run allows developers to build their app once (on physical devices, emulator or both) and as they change their code, AS does hot code swapping where it only updates the parts of the code that have been changed and the developer can see those changes after a second or two.
Since the built-in emulator has Google Play Services like a physical device, you can test a lot of API calls without having to deploy your application to a device.
Layouts are built and can be observed in real time and are automatically updated after every change. You can even see these changes on different screens.
For graphics-intensive apps or games, Android Studio has a GPU profiler baked in. With this you can see exactly what is happening inside the device when a new image is drawn on the screen.
Unlike it's predecessor, which is based off Eclipse, Android Studio is build on top of Jetbrain's Flagship Java IDE which offers over a number of features. It's also open-source too (Community Edition only).
Android Studio is the official IDE for Android and it works great as an Android IDE. Unfortunately, that's the only thing it can do, if you want to develop applications for other platforms in Java, you have to learn another IDE as well.
While the Android team have recently fixed issues that had to do with emulation on an x86 architecture and greatly improving emulator speeds, emulating an Android device and running apps on an ARM architecture is still pretty slow.
Many plugins are available for almost any task a developer may need to cover. Plugins are developed by Jetbrains themselves or by 3rd parties through the SDK available for writing them.
Uses a fast indexing technique to provide contextual hints (auto-completion, available object members, import suggestions). On-the-fly code analysis to detect errors and propose refactorization.
Uses a fast indexing technique to provide contextual hints (auto-completion, available object members, import suggestions). On-the-fly code analysis to detect errors and propose refactorization.
There is a free community edition (open source) and an ultimate edition, which you can compare here.
The ultimate edition is available for free for one year for students but must be registered through an .edu e-mail account.
IDEA places an emphasis in safe refactoring, offering a variety of features to make this possible for a variety of languages. These features include safe delete, type migration and replacing method code duplicates.
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.
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.
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.