Over on his YouTube channel, Aaron, creator of DragonOS and WarDragon has uploaded a video showing how it is possible to decode Meshtastic with an RTL-SDR and GNU Radio project called Meshtastic_SDR. 

If you weren't aware of it, Meshtastic is software that enables off-grid mesh network based communications and can run on cheap LoRa hardware. The mesh based nature of the system means that communications can be received over long distances, without any infrastructure, as long as there are sufficient Meshtastic nodes in an area that are able to route the message to the destination node. One example application of Meshtastic is to use it as a mesh-based text messaging system. This might be useful for teams of hikers, pilots, or skiiers who operate in remote areas without cell phone coverage.

In the video, Aaron shows how to install the Meshtastic GNU Radio software on DragonOS (Linux), and how to run the GNU Radio flowgraph and Python decoder script. Later in the video Aaron shows some test text messages being received by the software.

The Meshtastic_SDR project can also be used to transmit Meshtastic messages with an appropriate TX-capable SDR.