Importing and updating contacts
by 
To automate the import and update of contacts from one application to another.
Emails, SMS and voice messages
by
To automate the sending of messages between Digitaleo and your application.
What you can do with 
Synchronise your contacts on a one-way basis
For example: update a contact in Google Contacts when they fill in a form sent with Digitaleo.
Automate your SMS, emails and voice messages
For example: send an email to a contact with Digitaleo when the "lead" label is assigned to them in Google Contacts.