[pheeney]

Could this be used as a sort of sporadic consumer phone service? For example signing up for services that require phone validation but want to protect your real phone for privacy. Activate the SIM, signup, verify, then deactivate. Repeat if they don't recognize your device or when you need to re-verify. After hardware costs you would be looking at $2/mo any time you needed it.

Most other services I have looked at require a constant subscription. Or they are not a "real" number like google voice that can be detected and rejected. Or when you cancel and re-activate your previous phone number has changed so you can't re-verify without maintaining an active subscription. If the number is assigned to the sim then you can potentially rotate or have multiple numbers as well.

[gruez]

I suspect the phone numbers will still show up as a voip number, which is probably be an issue for sms validation.

[Nextgrid]

There are carriers out there that sell "real" numbers at least here in the UK. I'm sure the same exists elsewhere.

[stqism]

This will be an issue, fraud prevention systems targeted at reducing IRFS aren’t exactly a fan of VOIP numbers.

[Nextgrid]

I have tried the same with their previous offering called "Programmable Wireless" and both voice support was lacking abroad and SMS had an issue where you can't send arbitrary caller IDs for SMSs sent to the SIM (so if you receive an SMS on a Twilio number but process it in your code before deciding whether to send it to a SIM, or receiving an SMS on a non-Twilio number).