A softphone is a piece of software that allows users to make telephone calls over the internet via a computer or smartphone. It has all the features of a desk phone and typically expands the range of services you can access on a desk phone. Most importantly, a softphone allows you to take your work phone with you wherever you go. It can be installed on a laptop, tablet or smartphone which allows you to make (and receive) calls from your work phone number on your personal mobile, without using any personal mobile minutes.