Local Direct Dial (LDD) is an operator-enabled service that helps you save on your mobile phone bill when you call an international visitor in your country. Such a person, often called an inbound roamer, can be dialled locally, instead of having to make an overseas IDD call. The only known country where this feature is currently available is Singapore.SingTel Mobile was the forerunner to introduce this technology, being the first in the world. When using its services, calls made between local SingTel Mobile subscribers and inbound roamers on SingTel’s network are contained within the local SingTel Mobile network. Thus, bringing substantial savings for both parties on mobile phone charges.