It is a call which is made over internet protocol (VoIP). For example,
one can call using Google Voice to other recipient located miles away. Such
call can also be international.
A mobile dialer or a soft dialer is an application allowing the users of the cell phones to make VoIP calls via a mobile device with Internet connection. Such a thing of making call this way is called mVoIP or Mobile VoIP. This mobile dialer can be used by various companies trying to reduce the operational expenditures or by individual who just want to save extra money on the phone bills.