I was recently informed by Virginmedia that Smart Call is to be withdrawn. Although I only use it occasionally I have found it extremely useful when visiting family with poor mobile connectivity, and also whilst abroad on holiday. They suggested there is no demand for this due to the popularity of other applications, however I don't know of anything that would allow me to make calls to landlines using a wifi connection within my home call plan. Perhaps someone knows differently?
There aren't any random apps out there which take into account your VM call plan. I believe VM are referring to apps like Skype etc which allow calls to be made anywhere in the world and allow for free skype to skype calls.
- - - - - - Any opinions expressed by myself are entirely my own and do not represent Virgin Media in any way.