Android Apps are developed using the Java Programming Language. Software Development Kit (SDK) is available for free to developers which significantly reduces the development costs. Developed and Tested Android Apps can be distributed through Google Play Store.
Android Apps can be as simple as displaying some text on the screen to complex games like Angry Birds.
Although Android is built mostly in Java, it also has support for other programming languages and tools, giving app developers more options and ways to build their projects easier and faster.
Android Developers have an easy way to fix, improve and update their apps thanks to the facilities that Android tools provide them. Comments of users and reviews in Google Play Store go a long way in improving the apps made by the developers