Although you can create, host forms and landing pages from 3rd Party application/ software (other than Aritic PinPoint default) and get the contacts from these directly inside Aritic PinPoint through API / webhook integrations.
But, we discourage to follow this method of form/ landing page integration, because of the following reasons:
When you host your web forms and landing pages on 3rd Party application; other than Aritic PinPoint, then you would not be able to track the behavior of the incoming contacts. This happens because you don't have Aritic PinPoint tracking code on the form/ landing pages added. Even after form submission from the 3rd Party application, it would be quite hard to track the behavior of contact later on.
Further, without the behavior and tracking data of the contact, you will not be able to build complex Automation Workflows and campaigns effectively.