Yesterday I found a strange but funny bug on PhoneGap/Cordova 2.9/3.0.
It seems that if your proyect begins with a number then you won’t be able to add “android” as a platform.
Example
$ cordova create 100Project com.example.100project "100 Project"
$ cordova platform add android
[Error: An error occured during creation of android sub-project. An unexpected error occurred: "$ANDROID_BIN" create project --target $TARGET --path "$PROJECT_PATH" --package $PACKAGE --activity $ACTIVITY &>/dev/null exited with 1
Deleting project...
So the only solution is to change the project name so it doesn’t start with a number.
Happy coding!!