When a call to an Infocaller Virtual Number is directed to your mobile extension, Infocaller APP will recognize the call and pop up to give you information about the call and allow you to control it.
If your extension is configured to allow call control (which it is by default) you can control the call from the APP. You are able to put the call on hold, call another extension, alternate between caller and extension and transfer the call to the new extension. The app also allows you to send dial tones when accesing automated services. This functionality is described here.