Nelos vs CairnOS

Stay connected beyond cell coverage. Nelos is an offline messaging, location sharing, and tracking app for families and small teams using MeshCore-compatible LoRa radios. Message your team, see everyone on a map, find trackers, and coordinate even when cell service or internet isn’t available. No radio yet? Offline maps, location history, and personal waypoints work right away. Connect a MeshCore-compatible radio to unlock messaging, teams, trackers, and help requests. STAY TOGETHER OFF-GRID • See teammates and compatible trackers on one map • Send team messages and direct messages over LoRa • Track family members, pets, and personal belongings with compatible trackers • Find a tracker faster with Find Mode • Create Safe Zones and get alerts when a tracker leaves or arrives • Look back at every alert in Activity • Send help requests and coordinate responses with your teams • Create and join teams offline using QR codes READY FOR THE OUTDOORS • Download detailed offline maps worldwide • Mark campsites, meeting points, hazards, and other locations with waypoints • Review the last 24 hours of location history MORE WITH NELOS PRO Unlock multiple active teams, unlimited trackers per team, unlimited offline maps, and up to 90 days of location history with a one-time lifetime purchase. PRIVACY-FOCUSED No account required. No central message server. No ads. Your location never goes to our servers: it is shared only with your team, over LoRa, when you choose. Built for families, hiking, camping, outdoor adventures, travel, volunteer teams, festivals, and other off-grid situations. COMPATIBLE HARDWARE Off-grid communication requires MeshCore-compatible LoRa hardware. Download maps before heading out. Location updates and message delivery depend on your devices, radio conditions, terrain, positioning availability, and permissions. Help requests go only to members of your teams, not to emergency services or to Nelos. Nelos should not be your only means of communication or safety in critical situations.

Cairn is a companion app for MeshCore LoRa mesh radios. Pair your radio over Bluetooth or WiFi and send messages through a community-built network of radios and repeaters, with no cell service, no internet and no account. MESSAGING - Direct messages, channels and room servers in one inbox, with filters - Public, private and hashtag channels; share or join a channel by QR code - Delivery status, with retry for failed sends - Emoji reactions, @mentions, forwarding, search and text selection - Path details for each message: every hop on a list and a map - On-device translation of incoming messages - Chats kept on a Cairn touch radio come over to the app when you pair - Block contacts or channel senders, filter keywords and mute conversations - Optional link previews, with a warning for known malware links DASHBOARD - Battery, network, radio, GPS, contacts and chats at a glance - Sunrise and sunset for your position and the radio's temperature sensor - Radio presets by region, or set frequency, bandwidth, spreading factor, coding rate and TX power yourself NODES & REPEATERS - Saved and heard nodes, with search, sort, filters and a card or list layout - A page for every node, with a map, readings and quick actions - Log in to your repeaters and room servers to see status, telemetry, neighbors and an SNR map, then change settings, access lists and regions or use the remote CLI - Send commands to your own companion radios over the mesh (MeshCore 1.18 firmware) - Telemetry history charts kept on your phone - Contact groups, QR sharing and a manual path editor SPECTRUM - Live noise floor and packet traffic on your frequency - Signal margin, airtime share and packets per minute - With a Cairn radio: the radio's own Channel view, with its trace, density heat map and 24-hour noise floor MAPS & GPS - Mesh map with standard, satellite and topographic layers - Live traffic layer: the links packets crossed lately, and each new packet as it arrives - Download map regions for offline use - Radio and phone GPS side by side, with a compass and a navigation HUD that points the way to any node TOOLS - Network Health, Scan for Nodes, Trace Path, Line of Sight with terrain and Fresnel zone, RX Log and a CLI terminal - Sign and verify messages with your radio's identity IN THE CAR & AROUND iOS - CarPlay: a dashboard of your radio, mesh, messages and location, a GPS page, and messages you hear and answer with Siri - Siri and Shortcuts: check radio status, send a message or send an advert - Live Activity and Dynamic Island with connection, battery and unread count - Multiple windows on iPad MAKE IT YOURS - Choose a color, gradient or photo background with glass cards over it - Give any node a photo or a color: its type's color, one of twelve shades or any color you pick - Backup and restore, plus CSV and GPX export PRIVACY Your messages travel radio to radio. Cairn has no accounts, no analytics and no developer server. Nothing is sent to the developer. REQUIREMENTS Requires a LoRa radio running MeshCore companion firmware, connected over Bluetooth or WiFi. Maps, link previews and Line of Sight elevation use the internet when it is available. Requires iOS 18 or later. Cairn is free and open source software under the GNU GPL v3, built on the work of the open-source MeshCore app community. Source code is linked from our support page.