Tools as in say the Eclipse IDE where you can develope apps,
There are lots of apps that can be made in
java.
there are some steps to integrate andoid SDK in eclipse for that you can search.
Number of links available on internet.
Before you start creating Android application, be sure you have your development environment set up. You need to:
1. Download the Android SDK.
2. Install the ADT plugin for Eclipse (if you’ll use the Eclipse IDE).
3. Download the latest SDK tools and platforms using the SDK Manager.
Thanks
Atul Itankar
InfoCepts | www.infocepts.com