form_example.php

add_action( 'gform_after_submission', 'crb_send_dynamic_email', 10, 2 );
function crb_send_dynamic_email( $entry, $form ) {
	// Check for only Popup Form
	$custom_form = carbon_get_theme_option('crb_popup_form');
	if ($custom_form != $entry['form_id']) {
		return;
	}

	//Simple validation
	$email = $entry[2];
	if (!filter_var($email, FILTER_VALIDATE_EMAIL) === true) {
		return;
	}

	// Start Emailing

	//............
	wp_mail( 'avakulenko.2create@gmail.com', 'Test', 'Hello');
}