[sparrish]

Many carriers don't allow non-authorized devices like 4g modems to send SMS on their networks now. That's a recent change (last year).

[__d]

So now you need a phone, maybe with USB Ethernet, and you write an app that exposes a REST API, and you call that?

Not a great solution, I guess, but ... zip-tie/hot-melt the hardware into a box with a fan and I guess it'd be mostly as reliable as a Raspberry Pi?

Is there a cheap Android phone with an external antenna socket still?