Possibility to add a URL handler for an (android) app

I need a URL handler for an android app to work properly. A URL handler is used to register an application to be started directly from a browser, like `app://parameters`. To achieve this in general, *.desktop files in `/usr/share/applications` have to be edited or created. By now I have not found any documentation on how to set up those files in a correct way without jeopardising consistency of the system, though. Does anyone know about comprehensive documentation on this issue? As a feature request, I would like to have an interface to add and edit URL handlers and *.desktop definitions, best would be a GUI. This way you could also change your default browser easily. Documentation on .desktop definitions can be found here: http://standards.freedesktop.org/desktop-entry-spec/latest/ar01s10.html (thanks to [@r0kk3rz](https://together.jolla.com/users/4133/r0kk3rz/))