I'm looking for free software (or a web app that has a free tier that doesn't expire) that enables me to add users (i.e. email addresses) to a "workflow" / automation that contains a timeline with different branches of logic determining whether (and when) to send certain emails.
Each user will be on her own schedule in the series of emails. There can be different paths of if/else branching logic that check for the presence of "tags" associated with that user to determine which branch to proceed down (and therefore which emails to send).
I used to pay for an account at ActiveCampaign which attempts to do exactly what I'm hoping for (see the screenshot of a sample workflow), but their service was unreliable.
I'm already aware of Mautic (open-source PHP software) and have installed it but found it to be too buggy.
Basically, I'm looking for an alternative to ActiveCampaign, Mautic, and Infusionsoft (either free open-source software or a web app that has a free tier).