The Android SDK ships with numerous other tools. Many of which are used for special development cases. However, the tools listed above will be used with just about every project, regardless of the type of app being developed. For more information on these and other tools available, check out the Android Tools section of the Android website. Also, new tools and improved tools are released on a fairly regular basis, so make sure you keep all of the packages updated with the AVD and SDK Manager.
Finally, above and beyond the Android tools we've discussed, your best resource is the Android Developer website. Complete with up-to-date SDK downloads, source documentation, tutorials, technical articles, and the Android blog with the latest news, this website provides critical knowledge and support for Android developers.
What is your most useful Android development tool?