ADCST (Active Directory Contact Sync Tool) is a simple console application written in .NET that will connect to Azure Active Directory, enumerate users and then create Contact objects in an on-premises active directory (or delete them if required).

This tool aims to solve an issue where two disparate companies need to exchange contact info for usage in Exchange Online.

See the following Post for more Info: http://www.resdevops.com/2015/04/28/active-directory-contact-sync-tool-adcst/