I don’t think we can control it directly, but we can optimize the content structure so the email has a higher chance of landing in the main inbox.
It depends on your email content. From what I know, Gmail has its own algorithms that decide where your email goes. whether it lands in the inbox or the promotions tab.
I’ve used Salesforce and Mailchimp before for campaigns and reminders, where users can also subscribe or unsubscribe.
