MeshOS on LilyGO T-Deck: Standalone Off-Grid Messenger
MeshOS turns the LilyGO T-Deck into a standalone mesh communicator. No phone required. Full keyboard, GPS maps, encrypted messaging, and multi-hop routing in your pocket.
No cell towers. No internet. No phone in your pocket. MeshOS is new firmware that turns the LilyGO T-Deck into a fully standalone off-grid messenger.
The T-Deck has the hardware: ESP32-S3, SX1262 LoRa radio, physical keyboard, 2.8-inch screen. MeshOS by Andy Kirby puts a polished standalone interface on top of MeshCore. Type on the keyboard, hit send, and your message travels over LoRa through the mesh network. Miles of range, completely internet-free.
What MeshOS Actually Does
MeshOS is embedded firmware that runs MeshCore’s mesh protocol directly on the T-Deck. You get:
- Direct messaging with end-to-end encryption
- Channel/group messaging
- Multi-hop routing through repeaters
- GPS mapping with offline maps
- Full MeshCore terminal access
The T-Deck becomes a self-contained mesh node. Power it on, and you’re on the network.
The Interface
The chat UI looks like a modern messaging app. Speech bubbles, color-coded usernames, scrollable threads. You can switch between channels and DMs with tabs. There’s emoji support (about 30 right now), delivery receipts, and press-to-reply.
If someone sends a URL, MeshOS displays it as a QR code you can scan with your phone later. Clever workaround for a device with no internet connection.
Notifications work well. New messages trigger a popup, optional alert tone, and can wake the screen and keyboard backlight. There’s also an always-on lock screen mode that shows time, battery, and mesh signal strength.
Mesh Tools
MeshOS includes utilities you’d normally need a computer for:
Repeater Scanner - Finds repeaters in range and lets you whitelist which ones to use. Prevents your contacts list from filling up with every repeater the radio hears.
Last Heard List - Shows recent stations with signal strength, distance, and approximate location. Quick way to see who’s active nearby.
Mesh Signal Meter - Like cell signal bars, but for mesh coverage. Shows when you last heard a repeater and which one.
Trace Route - Follow your message’s path through the mesh. See each hop and signal quality at every step.
Noise Floor Monitor - Live graph of RF background noise. Useful for diagnosing why messages aren’t getting through.
Repeater Admin - If you run your own repeater and have the credentials, you can sync its clock, check stats, and trigger adverts directly from the T-Deck. No laptop required.
GPS and Mapping
The T-Deck Plus has built-in GPS (the standard T-Deck does not). MeshOS uses it to plot your position on an offline world map. The map includes major city names and multiple zoom levels, all stored in the firmware. No external tile downloads needed.
You can see other nodes and repeaters on the map if they’ve shared their coordinates. Pan and zoom with the trackball or touchscreen. The UK view includes a detailed outline showing active nodes in real time.
Higher zoom levels require the paid registration key, but the basic map works without it.
The Terminal
For anyone who wants to dig deeper, MeshOS includes a full MeshCore terminal on the device. Every packet, every routing decision, every acknowledgment scrolls by in a color-coded log. You can enter commands, log into remote repeaters (if you have admin rights), and watch the mesh work in real time.
The terminal output also mirrors to USB serial, so you can use a computer keyboard if you prefer.
Getting Started
Flash the firmware: Use the MeshCore Web Flasher or download the binary and flash via esptool. Takes a few minutes over USB. Make sure you pick the right frequency (915 MHz for US, 868 MHz for EU).
Initial setup: MeshOS walks you through three steps on first boot:
- Set your nickname
- Choose your region/frequency
- Keys generate automatically
After that, send an advert so others can see you, and start messaging.
Optional registration: Basic features are free. For £8, you can unlock deeper map zoom and remote repeater administration over RF. The license is tied to your device’s serial number.
What This Means
The T-Deck was already a capable piece of hardware. MeshOS makes it useful without a phone in your pocket.
For field work, emergencies, or anywhere you don’t want to depend on a smartphone, this is a significant upgrade. You get the full MeshCore network in a device that fits in a cargo pocket and runs all day on battery.
If you’ve got a T-Deck and want a polished standalone MeshCore experience, this is worth checking out.
Links:
MeshOS is developed by Andy Kirby. MeshCore is an open-source mesh protocol. See our MeshCore Getting Started Guide for more.
