It appears you can only trigger an action from a user interaction, like the click of a button - but you can’t trigger actions as a result of some data changing, or from an API call outside the app.
Example:
A form on a company website is filled in which adds a record to a table → send push notification to relevant user
OR
A record’s status is updated by one user → send email to another user
Even using Make and Zapier, I’m unable to set up any external automations involving Glide that don’t include some user behaviour-triggered activity from within the app.
As an automation enthusiastic (aren’t all Gliders?!) this seems to be the biggest weakest link currently… I’ve heard that automations are coming, but it’s been radio silence in terms of when this might be…