You must be a domain administrator in order to install the service on google apps.  The process takes 1 minute. 

I-Install the application

1. Install the application Evercontact from the G Suite Marketplace here.

2. Provide your domain's Google authorizations:

3. a-  Add as many of your domain users as you'd like. 

    b-  In your domain dashboard, you'll be able to access Evercontact as you see below:

  c- Launch Evercontact:

And as long as you didn't miss any steps, you should be all set.

For more information, check out our Evercontact for Google Apps documentation.