With the Cocoonmail API, you can easily manage contacts directly from your application or service. For example, creating a new contact is as easy as sending a POST request to https://app.cocoonmail.com/api/v1/contacts/create. 
{
  "email": "adam@cocoonmail.com",
  "firstName": "Adam",
  "lastName": "Kaczmarek",
  "favoriteColor": "blue",
  "userGroup": "Founders",
  "source": "Signup form Service"
}
We also offer endpoints for finding, updating and deleting contacts (plus some other features like sending transactional email and sending events). Go to our API reference for a full guide.