MeshSat

Standalone Android field gateway. Meshtastic, Iridium, APRS, SMS. No companion app, no cloud.

Getting started Pair your node. In Setup, open Your MeshSat node, tap Scan for Meshtastic devices, then Connect next to your node and enter its Bluetooth PIN. The scan lists every Meshtastic device in range, so pick the node by its name (a v0 node advertises as MSIR_ plus four hex digits). A plain Meshtastic radio pairs the same way. Satellite. With Use the node's modem on (the default), the app uses the node's RockBLOCK while it is connected. Setup > Satellite shows the modem, with Poll Signal and Check Mailbox, and a Node health card with what the node reports about its own modem: who holds it, its last signal reading, sessions and their results, and the node's own satellite routing. After a restart the app reconnects to the same node and takes the modem back by itself. Hub (optional). Setup > Hub > Scan the Hub's QR code, with the QR code from the Hub. That sets the Hub address, credentials and client certificate. SMS. In Setup > SMS, tap Allow SMS and fill in the Kit phone number. Emergency contacts. In Setup > Safety, add the people an SOS goes to by SMS, then tap Test the alarm to see every route work. Send something. In Messages, tap New message and pick who it is for: a node, everyone on the mesh, a phone number or the satellite. For a satellite message the compose bar shows the bytes and credits before you send. Home shows each way out: a solid line works, a dotted line is not available, and an orange dot is a message on its way. On first launch a welcome page says what each Android permission is for before Android asks, and Home keeps a Getting started list of these steps until they are done.

Routing rules (Setup > Advanced > Routing rules) decide what is forwarded between links automatically, for example mesh messages out by satellite.

What it does Mesh. Meshtastic over Bluetooth LE with the official protobufs: text, positions, telemetry, waypoints, node info, traceroute and more. A reply to a node goes to that node, not to the whole channel. People lists the nodes you hear, with a button to message one or show it on the map, and Mesh topology draws how they are linked from their neighbour info. Region, channels and transmit power are under Setup > Mesh radio settings; the app only sends back values it has read from the radio. Satellite. Iridium SBD through the node's RockBLOCK 9603, up to 340 bytes out and 270 bytes in. Messages wait in a queue and are retried until they go out, and a message that arrives during any satellite session is stored straight away. The app opens a satellite session only when there is something to send, when the modem rings, when the gateway holds a message and the modem sees a satellite, or when you tap Check Mailbox. It never checks on a timer and never because it reconnected to the node, because every session costs a credit. If Bluetooth drops in the middle of a session, the node finishes it on its own and the app treats the message as possibly sent and retries it after the modem's 3-minute pause. Passes are predicted on the phone from orbit data that ships with the app and is refreshed when there is internet, and the signal shows as an icon in Android's status bar. RockBLOCK 9704 (Iridium IMT) over an HC-05/06 Bluetooth serial adapter, with messages up to 100 KB. The code is there; it has not been tested on hardware. SMS through the phone's own SIM, optionally encrypted per conversation with AES-256-GCM. Mesh and SMS messages are compressed with MSVQ-SC by default. It is lossy: what arrives means the same, but may not be word for word what was sent. APRS through a KISS TNC over TCP (Direwolf, for example) or directly to APRS-IS, with smart beaconing and acknowledged messages. Hub. MQTT with a client certificate. The phone shows up in the Hub's fleet like a field kit, reports health and positions, and takes remote commands: send a message, flush the queue, update config, rotate keys, reboot. When a field kit cannot be reached directly, the app can reach it through a tunnel via the Hub. TAK. Positions from the Hub's TAK feed appear on the map. Receive only. Reticulum. The phone runs as a Reticulum transport node and relays between the mesh, both Iridium modems, MQTT and TCP peers. Safety. Hold the SOS button on Home for 3 seconds. The SOS goes out on every route the phone has, each one retried until it is sent: by satellite as the Bridge's SOS frame, which the Hub raises as an alarm; as a mesh broadcast, which any MeshSat kit in range relays; by SMS with a map link to each emergency contact; and to the Hub over the internet. It stays on, with a banner on every screen and a line per route saying where it stands, until you cancel it in the app or from the notification. Everyone who got it is then told you are safe. Test the alarm uses the same routes with a text that raises no alarm, and a position report instead of the SOS frame by satellite. A check-in timer sends SOS if the phone sees no activity for too long, and zones, drawn on the map, record when a mesh node enters or leaves an area. People you carry. Swap contact cards face to face: one phone shows its card as a QR code under People, the other scans it, and both read the same fingerprint off their screens. The card is signed by the phone that made it, so it cannot be altered on the way, and the fingerprint you read aloud is what says the card is really theirs. A card that arrives as text instead of through the camera is kept, and marked, as imported. Records. A message queue with everything waiting, sent or given up, and config export and import in YAML or JSON, in the same format as the Bridge. Local API on 127.0.0.1:6051, for testing and automation. The map works without internet down to country level, from a world overview built into the app. The gateway runs as a foreground service, so the phone keeps relaying with the screen off; to have it start again after a phone restart, switch on Start after a phone restart in Setup > Advanced > Diagnostics (off by default). Night mode, the moon on Home, turns the whole app red to keep your night vision.