This is useful service when you do not want to display the actual number of one person to another. Let’s say driver from taxi booking app is calling the customer for asking address of pick up, here the taxi booking app will hide the driver’s real number to customer. This way number privacy can be managed and no direct contact between parties. This is very useful and popular use case for delivery apps, car booking apps etc. where no direct contact is getting displayed when calling. This is called number masking between parties. A some DID number is mapped between driver and customer so if they call that common number they can reach one another without displaying actual number.