The standard development tool for Android is the Android SDK, you can check on link.
The operating system as a whole was thought to run Java applications and so it is a bit difficult to get away from it. There is the possibility of running native code, in C language, but this is little recommended by Google. Even so you wouldn’t develop end-user applications without using Java, but in general only libraries.
About database need, for local base you probably want to use Sqlite. Otherwise it will probably use some web service technology.
There is a version of Eclipse IDE that integrates the Android SDK where you can preview your work, which makes the work be, at least regarding user interface development, more productive.
The default is Java, but I know it is possible to program in C# and Delphi (I don’t know with what limitations). Do a search.
– Piovezan
Take a look at this alternative: http://xamarin.com/ (I have no affiliation with the company, not even use the product). For some people it may be a better alternative.
– Maniero
http://answall.com/tags/android/info
– Androiderson
Upgrading, in addition to Java it is also possible to program in Kotlin.
– Piovezan