A few years ago, James Provost built a handheld texting device, based on Arduino, to send short messages over a connected ham radio set. One of my many backburner projects has been to build something similar, either based on amateur radio (like James’s project) or based on LoRa. Little did I know that Kevin Hester, another embedded engineer, had a similar idea around the same time. Kevin created Meshtastic as a grassroots, community-driven project to enable communications during emergencies or areas without internet/cell coverage.
Meshtastic is an open-source project that turns inexpensive LoRa radios into a long-range, off-grid messaging network. Devices relay short, low-bandwidth messages between themselves, hopping across the “mesh” until a message reaches its destination. Because it uses unlicensed ISM bands (region-dependent) and tiny amounts of power, you can carry a device for days and stay in touch without cellular or Wi-Fi coverage. Think of it as “texting for dead zones,” built by and for the community.
Under the hood, a mesh forms when nearby nodes share the same radio parameters (center frequency, bandwidth, spreading factor). Each node can connect to a phone (typically via Bluetooth) for a familiar chat interface, while the radios handle store-and-forward relaying in the background. Meshtastic supports multiple client apps (Android, iOS, web, CLI) and runs on a range of microcontroller boards with LoRa chipsets.
Security is built in. Payloads are encrypted (AES256-CTR for channel encryption) and the project has steadily improved its crypto over time, including public-key features for direct messages and admin actions. As with any over-the-air system, headers remain visible so the mesh can forward packets, but contents stay private to those with the key.
The project has been steadily gaining popularity over the past few years. WIRED published the article The Texting Network for the End of the World a few months ago, and I only recently learned about the project’s existence.
At this time, the project still feels very much like a new way to engage with technology and has not quite hit regular consumers yet. To be honest, it may never reach mainstream adoption. I’m OK with being one of a few hipsters at tech conferences sporting my Meshtastic badge hanging from my backpack.
How does it work?
Each Meshtastic node uses LoRa (a chirp-spread-spectrum modem) to send small packets at very low data rates. Lower data rates buy you distance and penetration, and higher data rates trade range for throughput. Nodes that “hear” a new packet rebroadcast it according to the mesh algorithm so messages can traverse multiple hops. The magic is in tuning radio parameters and strategically placing nodes to achieve the desired coverage.
On the user side, you’ll pair your phone to a node (typically over Bluetooth), pick or create channels (which define encryption keys and settings), and chat in groups or one-to-one. Advanced users can add gateways (MQTT bridges), GIS mapping, and sensors, but the core experience is deliberately simple: send short texts when nothing else works.
In most cases, you use the Meshtastic iOS or Android app to send and receive messages. However, because the messaging layer is open source, you can find a host of community-provided libraries that allow you to build your own, custom software. For example, here is the Meshtastic Arduino library. Go wild building your next cyberdeck to communicate over LoRa!
So, what can you do with Meshtastic?
Most use cases I see involve texting family and friends in areas with little or no cell coverage, such as in parks, hiking, and skiing. Most portable nodes can easily reach a kilometer or two. Battery life varies among the hardware vendors, but you can usually expect one or a few days for a personal node.
I’ve also read about conference and festival goers dropping a node in their backpack or pocket to keep in touch with their friends. Cell coverage and internet can be spotty or under too much load in such crowded environments, and the lack of activity on other ISM bands means you can text freely.
Have a friend in your neighborhood? A personal node or stationary node placed just outside your home could allow you to text them outside of regular methods, such as SMS, Signal, etc. A bit frivolous, but it might rekindle those nostalgic moments of using a tin can phone to talk to your buddies in a tree house.
Finally, Meshtastic might be an important backup for emergency (“End of the World”) types of situations where power, cell towers, and even landlines go out. While it’s not a complete replacement for amateur radio or public-safety systems, it offers a valuable supplement for short texts in your group. Additionally, you don’t need an amateur license to operate Meshtastic devices on an ISM band!
Tradeoffs
Meshtastic does not solve all off-grid texting woes. There are some tradeoffs you should consider:
Strengths
- Off-grid reliability: Completely independent of cell/Wi-Fi infrastructure. Great for planned outings, backcountry safety nets, and event comms.
- Long battery life & cost: Low-power radios and microcontrollers mean long runtimes on small packs; hardware is relatively inexpensive compared to satellite messengers.
Privacy by default: Channel keys encrypt payloads; recent versions add public-key features for DM/admin security. - Community velocity: Active devs and users, frequent firmware and tooling improvements, and abundant how-tos.
Limitations
- Bandwidth is tiny: In case it was not clear, this is not the Internet. Messages are short, and as a result, congestion can happen at big events if settings aren’t tuned.
- Mesh density matters: A single node can’t do much. Place relays smartly (height is might) and recruit your friends.
- Line-of-sight physics: Hills and buildings block. Expect a couple of kilometers per hop in average terrain unless you elevate nodes and antennas.
Getting Started
To start your Meshtastic journey, you’ll need a node device. Here are some of the popular models recommended by the community.
Full keyboard decks allow you to send and receive text messages with just the device.
- LILIYGO T-Deck Plus Meshtastic – rock that old Blackberry look as you text away with this handheld!
App-based nodes require the Meshtastic app, typically connected over Bluetooth to your phone.
- Heltec WiFi LoRa32 V3 – based on the ESP32, the Heltec V3 is a great, low-cost starter device that’s perfect for tinkering and building your own case. Note that the ESP32 is often considered more power hungry than other wireless chipsets, so your battery life might be limited.
- Seeed Studio SenseCAP Card Tracker T1000-E – a fully enclosed, water resistant, off-the-shelf node ready to go
Stationary nodes can act as a relay and boost your coverage. You can even pair them with solar panels and a battery for long-term, maintenance-free operation!
- RAK WisBlock – Well-loved in the community for its expandability, power efficiency, and build quality. You can also buy add-on kits to turn it into a solar-powered permanent installation!
Once you receive your kit, you’ll want to follow the Meshtastic getting started guide to flash the firmware (if not factory flashed), configure the node via web client, install the app, create a channel, and invite your friends.
Final thoughts
While I have not personally played with Meshtastic yet, I have ordered the T1000-E. I plan to tinker with it at Hackaday Supercon and see if anyone is texting over the Meshtastic network. After the event, I plan to share my findings and experiences with Meshtastic.