The contact manager is a contact-centric database and software program being used in most smartphones using the vCard as the main reference standard for data.
They are contact-centric databases that provide a fully integrated approach to tracking of all information and communication activities linked to contacts. A contact manager is a software program that enables users to easily store and find contact information, such as names, addresses and telephone numbers. Simple ones for personal use are included in most smartphones. The main reference standard for contact data and metadata, semantic and interchange, is the vCard. 
