If you want to create apps for Android, Android Studio is the best development environment for this. Launched in 2013, this program can be downloaded for free and it comes with lots of great features. You can download it on Windows, Linux and MacOs and you can benefit from many cool features:
- A reach layout editor where you can drag and drop components;
- An Android Virtual Device for testing;
- Some templates that help you to create great designs;
Being an open source program, you can contribute to do it better, if you have the knowledge for this. To run this program your computer should have at least 3 GB Ram and 2 Gb disk space.