Change default package from com.example for Eclipse Android projects
No, you cannot change the default; it's hardcoded in the plugin sources.
(For the curious, it's in com.android.ide.eclipse.adt.internal.wizards.templates.NewProjectPage#SAMPLE_PACKAGE_PREFIX in the ADT code base). We should consider persisting the most recently set package prefix and inserting the parent package next time. Feel free to file an issue for that at http://b.android.com category Component-Tools.
-- Tor
With Android Studio not running, edit the file: C:\Users\MyAccount\.AndroidStudio\config\options\options.xml (replace C: with the installation drive and MyAccount with your account name).
Within the xml file look for "property name="SAVED_COMPANY_DOMAIN" value=" and change the value to what you want.