Used for task management, file management, emulator interaction, logging and screen capture.
You can use DDMS file explorer to browse files on the emulator and a device ( phone). As well as copy files
to and from them.
DDMS can simulate calls , text messages and location to the emulator but not to an actual phone.
control F11 and control F12 for portrait and landscape orientation of the emulator.
Alt-Enter for full screen view.
Source code ( which I assume they mean Java code) goes in to the /src folder. I am not sure if it is only allowed there or can be placed in other folders as well. If it can be placed in other folders, when should you?
Tools can be found in the /tools folder ( makes sense). You can fine such tools as draw 9-patch which is used for making buttons that are stretchable .
Android documentation is in the /doc folder. The documentation is not up to date but a good place to start if you don't have access to the internet at that moment. You have to go to the website for updated documentation.