The issues other people are describing with insecurity and lack of ack could also be resolved. The backend server that accepts messages could even support WCTP for backwards compatibility.
I'm thinking of building a Pager with the pygo2 once it finally hits the market: https://pycom.io/product/pygo2/
It's got LTE-M which is perfect for this, and LoRa and SigFox as backup. A year's service is about $40
Unfortunately it's not untracked like the old pagers were but in return it should do confirmations and even replies somehow. I'll have to add a beeper/vibration motor and a stronger battery perhaps but I think it'll work.
That's a good plan. Tracfone is roughly $10 a month for a smartphone, but what I wish existed was (a) a really cheap device and plan that was SMS-only and (b) people would only use SMS.
I'm damn sick of Fidelity leaving messages for no doubt wondrous investment advice and robocalls for appliance and car warranty programs. That's 99% of the voice calls that I get.
A year of unlimited talk/text from Liberty Wireless (a T-Mobile MVNO) costs $60.^1 Then, use call barring/do not disturb to disable incoming calls and USSD codes^2 to turn off call forwarding. You now have a phone number that effectively only supports SMS.
I'd also recommend going with this plan if you are addicted to the Internet and just want a phone, but don't want to pay through the nose for something like the Punkt^3.
As far as only using SMS, sending/forwarding emails through SMS is doable (for now), so if your people's comms can be converted to email, you can use SMS for those as well.
Unfortunately, the naive solution of sending outgoing mail requires MMS (and therefore data), but you can send SMS to a Google Voice number, for example, which can be set up to forward a copy of the message to an email, which can then be used for triggering control events locally. YMMV.
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1 - https://www.ebay.com/itm/174582899616
2 - https://www.t-mobile.com/support/plans-features/self-service...
While the SMS integration is going away soon, you will still be able to use (I think) SMS from within the app and while the terms of service disallow automation, my understanding is that is mostly only for outgoing texts (they don't want Google Voice users spamming the world) rather than incoming (I don't see why Google Voice would be against you doing whatever you want with the texts you receive).
I suspect the reason why carriers allow these spam calls and texts is they make money from all calls and texts and have no incentive to fix things.
https://www.androidpolice.com/2021/03/09/google-voice-wont-f...
I use SMS-via-email very frequently, and was rather worried. Thankfully that will stay.
SMS forwarding to a local number's SMS hasn't been possible for me anyway, because my local number is not in the US. At one point I had a setup with Google Calendar forwarding my emails to SMS, but that got shut down in 2019 (to my dismay).
https://www.ghacks.net/2018/11/19/google-removes-sms-notific...
BSOH proverb
- Whitelisting my messaging app means I'd still get pinged for non-emergency messages
- Enforcing the block at the software level makes it too easy for me to disable it when the temptation arises. My current setup forces me to walk upstairs, flip the switch, then wait multiple minutes for the router to boot.
It would also take a lot more effort to set up, and time is money!
I was surprised to find that, as the article mentions, there's basically only one place to buy new pagers -- and they're quite expensive. After thinking about it some more, I realized that what I really wanted was a separate phone number that my team could send SMS messages to. And I didn't even need to build my own pager-like device out of a RasPi or something; I could just buy a cheap flip phone. Total cost for phone and 1000 SMS messages is <$100.