The Kit add-on needs to be installed and activated to see the features mentioned in this this documentation.
Connect to your Kit Account to Ninja Forms
In order to enable communication between your WordPress site and Kit (formerly known as ConvertKit) you need an API key to connect both system. The Kit API Key is available in the Kit Account Settings Page.
Then go to Ninja Forms > Settings > Kit and past in your API key.
Send your Form Data to Kit
To add the action to any form, from the Emails & Actions tab click Add New Action and then the Kit action from inside the Actions Window that opens.
Configure the Kit action
Version 3.1.1 of Kit gives you the abiity to add multiple actions to a single form, each connecting to different ConvertKit accounts! If conditional logic is activated, then these actions can be used to connect to different accounts conditionally.
To enable navigate to Ninja Forms > Settings > Advanced Settings > tick ‘Dev Mode‘. Enabling this feature will give you access to the Advanced settings within Ninja Forms.
API Key
Add an additional Kit API key in conjunctions with conditional logic to connect your form with more than one Kit account.
Debug Mode
Turn on debugging to see that data is being sent to Kit through their API.