If you will develop and maintain this app, use the author prefix, else use a company or department prefix.
\author\software
\author\software\package
\company\software
\company\software\package
Namespace use-cases as examples:
Symfony They use a subnamespace "Component", just to have a clear folder structure.
namespace Symfony\Component\BrowserKit;
Zend They use Company\Component.
namespace Zend\Authentication;
But my suggestion would be to use namespace RWS\PackageOne;
.
Keep in mind that the namespace reflects your folder structure (PSR)!