[babebridou]

You don't need to "own the domain", strictly speaking, you need to use a unique package identifier. Owning the domain and using it for package naming is a good enough convention and helps avoid conflicting identifiers.

Java package naming convention http://en.wikipedia.org/wiki/Java_package#Package_naming_con...

Useful Stackoverflow discussion http://stackoverflow.com/questions/6273892/android-package-n...

If you don't own any domain, get one, it will help you tons and you can recoup the cost by passing on a cup of coffee every other sunday morning.