It’s $10 per month for my Garmin InReach which gives you emergency comms and let’s you upgrade to unlimited SMS and some other stuff for $60. I use it a lot and it’s very reasonable. Runs on Iridium.
I have a Garmin InReach too, but to say it’s “satellite phone internet” is a stretch. You can send little blips of data. There’s no phone service. Nor is there any internet service.
If you read the T-Mobile announcement, that’s exactly what you’ll get. Not saying it’s not great but I think people
have the misconception that they’ll have usable satellite internet which is really not happening due to physics.