what is a sub-user account

Sub-user account is basically a subordinate account (a separate account) where you've shared your form submissions and its data. When a sub-account creates a form, it is accessible by the master's account.

Here's a guide on how to share a form to your sub-account user http://www.jotform.com/help/232-How-to-Share-Forms-with-a-Sub-Account-User.

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