Both, depends on your plan. Custom messages cost more. My $10/month-ish plan allows unlimited pre-canned, which I use to check in with family “I’m still alive”

Both, depends on your plan. Custom messages cost more. My $10/month-ish plan allows unlimited pre-canned, which I use to check in with family “I’m still alive” / “on my way home” type thing. Then I get a certain allocation of custom. Sending GPS waypoints counts as custom IIRC?