I’m looking for clarity on how to filter and trigger Twilio messages via attribute.
My current setup is that there are 20 users and the first 19 have no attributes. Upon learning how to set attributes, the most recent user has these set.
When using the Broadcast > Receive an Email trigger, do I place the filter on the trigger action or on the following action, which in my case will be the Twilio Send SMS?
Hi @inviz,
You can actually put the filter on either the trigger or the action. We would normally advise adding it to the trigger however to save on interactions used as triggers that are filtered (so that the flow doesn’t run), do not count towards your interactions. This includes broadcasts - if you use a filter on your broadcast (for example to filter out all subscribers who have a certain attribute set) then you’ll only be charged for the broadcast interactions that triggered. 
There’s a tutorial here that might help on setting up subscription broadcasts too.