Signup form integration option?
Background:
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We have a public website A and our application web site B. We want to track user behaviour and info all they way through the buying cycle as the user will go through a free trial on web site B. We are able to use webforms integrated on site A to capture Demo Video signup and other sales related stuff. However once a user goes to sign-up for free trial, this is done on site B using custom code (we have different important validations and registrations). Thus a Zoho web form will not work in this case. However we want the signup information to be associated with the site A behaviour from Sales IQ and anything else the user has done in the past.
Question:
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What is the best way for us to integrate our custom sign-up form with Zoho CRM to make sure all context information from past visits and SalesIQ is keept intact for the given visitor?