Meshtastic runs on these: https://www.aliexpress.com/item/4000897355282.html https://www.aliexpress.com/item/4000897355282.html And if you don't need GPS (the

Meshtastic runs on these: https://www.aliexpress.com/item/4000897355282.html https://www.aliexpress.com/item/4000897355282.html And if you don't need GPS (they'll use the GPS in an Android phone), these too: https://www.aliexpress.com/item/4000329729312.html https://www.aliexpress.com/item/4000329729312.html You could save a buck or two more by getting ones without screens, but it makes Bluetooth pairing more complex (you need to read the pairing code off the serial console over the USB port. But yo only need to do it once. It's not _awful_ if your plan is always to pair each device with the same (Android) phone)