This has been a problem with many situations from power outages, fires, floods, wide internet and cell outages or lack of coverage, and many other events that causes both cell and internet outages. There are many ways to send and receive text messages without cell and internet.
I began investigating how I can send and receive text messages without cell or WiFi a while ago, and there are several ways of doing so. One caveat is if the Internet is down on the planet, the options are limited but still exists. Unfortunately, one of my favorite ways to do it is no longer available (at least until someone else picks up the project and restarts it) but I will still list it here.
SMSGTE (Currently not available)
Pronounced “SMS Gate” this is a messaging platform that allows you to send short SMS messages to phones. It uses APRS on some amateur radios to send the message to an iGate gateway, which then forwards it to an SMS gateway to send a text message to a cell phone. The requirement for sending and receiving is that local Internet is available to the iGate gateway and the SMS gateway, and the receiving cell phone has at least limited cell coverage.
Winlink
This is an e-mail platform that allows you to send messages using amateur radio, a TNC device, and a laptop. This supports multiple amateur radio bands to send and receive e-mail messages. You set the radio frequency to a Winlink gateway, use the computer to construct the message, then open the connection via amateur radio, and send/receive the message.
Rattlegram aka Ribbit (Android and iPhone version in testing)
Plays back the message as data on the phone and using amateur radio, can send that to a recipient who also has Rattlegram/Ribbit on a cell phone and a radio. Does not need cell service or WiFi to work. Just set the radio frequency the same as the sender and recipient, and as long as both have the radio on the same frequency and have a cell phone with Rattlegram/Ribbit app, messages can be sent and received. Check out this Ribbit post.
GoTenna Mesh (Availability issues today)
This is a small dongle that you hang on a backpack to connect to a mesh to send SMS messages between peers. You pair the GoTenna mesh device (using Bluetooth) to your cell phone and other people on the mesh can receive messages. The range isn’t far unless there is a large mesh that can extend your reach. You and the other person just need the GoTenna app and the GoTenna Mesh device. The app is $9.99 a year.
Meshtastic
This is a small device that you either DIY build or buy pre-built by hobbyists or from LilyGo that will allow you to pair (using Bluetooth) to a cell phone or tablet (iOS or Android) and send short SMS messages between others on the mesh. This is very similar to GoTenna Mesh, and you create a mesh network for sending short SMS messages. The major difference is that this is open source, lower initial startup cost (I setup a pair of Meshtastic devices for under $100), and the Meshtastic App is free. The drawback is you may need to be a bit technical to get started, but once you do, it is as easy as pairing the device with your phone or tablet, opening the app, selecting the recipient and sending the message. If you want to build one, I have a comprehensive build and configure your own Meshtastic communication device here.
APRS Messaging
APRS equipped radios to send short messages to other APRS devices. Short messages that can be sent with APRS, but everyone sees it. You can use APRS with SMSGTE (not available today) and send e-mail messages, but this is also cleartext.
Zoleo
Iridium based satellite messaging platform. Unlimited $50.00 per month (no annual contract discount at this time). You buy a Zoleo device, pair it via Bluetooth to your phone via the Zoleo App, and begin sending messages. If you don’t have the unlimited plan, you will pay per message after the allotted quota is exceeded.
Garmin InReach
Iridium based satellite messaging platform. Unlimited $64.95 per month or $49.95 per month with annual contract. This is very similar to Zoleo. You buy a Garmin InReach capable device, pair it via Bluetooth to your phone via the Garmin Explorer App, and begin sending messages. If you don’t have the unlimited plan, you will pay per message after the allotted quota is exceeded.
Satellite Phones or Hotspots
Iridium Go or any of the other sat phone service provider to send SMS. Between $0.10 to $0.25 per text message based on service plan. Very similar to Zoleo and Garmin InReach, pair via Bluetooth to your device, open the corresponding app and start sending messages.
iPhone 14 and newer
There is the SOS function that allows you to send text message to get help. This is for emergency use only, and uses satellite to get assistance in an emergency. This is not for texting your friend when your cell phone has no service, no wireless, and it says SOS on the top right corner of your phone.
I will update this list if I see other options that I test. Also, if I missed any others, please provide feedback and I will add it on this list.
