I’m trying to figure out a way to send a group message. Sending a SMS is trivial, there’s a specific action. However, when I try to send a message to “650-123-4567, 650-234-4567” as an example, the behavior defaults to just composing a message to the first number.
This might not be anything I can do on Airtable’s side, and more to do with how Messages handles incoming requests. But curious if anyone has had luck with this!
To be clear, are you using some sort of service or integration to send an SMS message, or does you action just open your messaging app? If it’s the later, have you tried different delimiters, such as a semi-colon (;) ? It’s probably going to largely depend on the messaging app, and what it allows or doesn’t allow.
Just using the action “Compose SMS” native to Glide. Will try some other delimiters, but you’d think that iMessage would support that!
It seems like the delimiter is just a comma, which is what I used 
I don’t use Apple products, so I can’t verify either way, but here’s a few other forum posts related to this:
I actually just figured this out! You need to create a joined list column with the phone numbers you want for a given text, with the numbers separated simply by a comma (no spaces). Then create a template column where you add in the following url to the start: sms://open?addresses=. I noticed that the number needs to be formatted XXX-XXX-XXXX; without the dashes it doesn’t work. (not sure if it handles parentheses or country codes).
So the data in your column would look like sms://open?addresses=555-555-1234,555-555-5678,555-555-9012. Then in your button, create an Open Link action on the button, and the link should be that sms://open?addresses=etc column.
This works in iOS. I wound up creating a second button for Android that uses the Compose SMS action pulling just from the joined list (without the sms::// url). Not sure how (or if it’s possible) to combine the buttons and make them conditional on the user’s device; I’m assuming not possible.