Not actually as hard as you'd think; almost every new product in the Salesforce suite was once a separate company and they managed to integrate it just fine. W

Not actually as hard as you'd think; almost every new product in the Salesforce suite was once a separate company and they managed to integrate it just fine. When the startup I was working for was acquired, we first integrated with Salesforce's SSO which was very easy, and kept having our clients use it as a separate product. Then, we rebranded the UI to look and feel like Salesforce, and changed the product name to fit. Only after all that did we start looking into moving to their url and fully integrating into the product suite.