Characteristics

• It must do something an ordinary user would like to do.
• It must have a good user interface, something ordinary users are familiar with.
• It can be included in popular system distributions and/or easily installed with a mere button push.
• It must fit in the environment. On Windows it should behave like a Windows program, on Gnome it should behave like a Gnome program. Likewise KDE, MacOSX, Android and so on.
• It must be capable of maintaining private data, e.g. for configuration and state. Platform conventions must be obeyed.