There's LoRa runs on 450/900 MHz with complete stack for transmitting and relaying messages. There's even modern encrypted protocol (meshstatic) built on it.
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First responders have awesome tools. But in tough situations, even common folks need to help.
After what happened in Myanmar, we need something like this that works properly.
It has only been tested in controlled environments. It can also be improved; I know BLE is not _that_ effective under rubble.
If you have any feedback or can contribute, don't hold back.
Cross-platform bluetooth between Android/iOS is too annoying sadly. If LoRa can help address those issues, it would simplify things a lot.