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Android Studio is an integrated development environment (IDE) from Google that provides developers with tools needed to build applications for the Android OS platform. Android Studio is available for download on Windows, Mac and Linux. A one-time, $25 developer's license is required to publish apps to Google Play App Store. The foundation for Android Studio is based on IntelliJ IDEA.
The Android Studio IDE is free to download and use. It has a rich UI development environment with templates to give new developers a launching pad into Android development. Developers will find that Studio gives them the tools to build phone and tablet solutions as well as emerging technology solutions for Android TV, Android Wear, Android Auto, Glass and additional contextual models.
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Pros
Pro Uses the powerful Gradle build tool out of the box
Android Studio uses Gradle as the official build tool for projects, moving away from the now outdated Apache Ant.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.
Pro Extremely easy to integrate Google Services
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.
Pro Officially supported by Google
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.