Haven't you been in trouble with exchanging contact information each other?
“linkle contact exchange” is the best application to exchange phone number or mail address.
It is very easy to exchange contact information by the same keyword.
Even the other party doesn't have this application, you can send your contact information to the other party through SMS, E-mail, messenger by this application.
It is the best solution to exchange among group members or via internet, in the long distance.
It can be used properly to tell contact information such as private, business, first contact by the other party.