Geoid Altimeter vs APRS Tracker Digi iGate

Geoid Altimeter is an elevation tracking tool built for field professionals. It applies high-precision geoid models to your smartphone's GPS ellipsoidal height to display a practical "orthometric height" (elevation above mean sea level). Try all features completely free for the first 30 days. Experience the convenience directly on your smartphone. [ Key Features ] - Orthometric Height (H = h − N): Converts the raw GPS ellipsoidal height using national or global geoid models. - High-Resolution Elevation (DEM): Reads terrain elevation for your current location or any pinned point — no need to physically stand there. - Pin & Address Search: Drop a pin or search an address to check the elevation anywhere on the map. - Favorites & CSV Export: Save sites with custom names and export all values (h, N, H, DEM) as CSV. - Model Comparison: View your local model alongside the global EGM96 reference. - One-Tap Copy, Screenshot Share, Transparent Satellite/OSM Overlay, and Compass. [ Supported High-Precision Regions ] Geoid models (orthometric height correction): Japan (Geoid 2024 / GSI), United States (GEOID18 / NOAA-NGS), Canada (CGG2013a / NRCan), New Zealand (NZGeoid2016 / LINZ), Switzerland (CHGeo2004 / swisstopo). High-resolution elevation (DEM): Japan (GSI, 5 m laser mesh), United States (USGS 3DEP), Switzerland (swisstopo), France (IGN RGE ALTI, 1 m). For every other country and region, the app provides seamless worldwide coverage using the global EGM96 geoid and global terrain-elevation data. [ New in 1.4.0 ] - Works beyond coverage: pre-load the national geoid model around you, and elevations stay on that model when the network goes. - Always says which model answered — the national service live, a value saved nearby, or the global EGM96 standing in. - Stand-still averaging: hold still and get a mean with its spread, instead of a single fix that scatters by metres. - Antenna height: set the pole length or how high you hold the phone, and it is subtracted from every GNSS height. - Height difference and grade (% and 1:n) between two saved points, a one-page PDF elevation record, and NGVD29 readings for US drawings levelled before NAVD88. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Stay visible. Stay connected. This app is a tool for radio amateurs, civil defense volunteer teams, and operators using the APRS protocol in field activities. The app allows you to transmit your position to the APRS-IS network via the internet and also operate directly via radio using AX.25 packets with 1200 AFSK modulation. It can be used for individual tracking, local communication, and supporting the infrastructure of an APRS network. Whether in expeditions, amateur radio events, travel in remote areas, or search and humanitarian aid operations, APRS Tracker provides features to track stations, share points of interest, and expand APRS coverage. KEY FEATURES APRS-IS Tracking Send your GPS coordinates to APRS-IS servers via the device's internet connection. Positions can be tracked on compatible public services, such as aprs.fi. AX.25 / 1200 AFSK RF Mode Transmit and receive APRS packets through the device's audio input and output. With a radio and a compatible audio interface, you can operate via RF even without internet access. APRS Digipeater Use the app as a digital repeater to extend the range of stations in the area. The Digipeater processes paths compatible with New-N rules and includes controls against loops, invalid paths, and duplicate packets. iGate Mode Forward valid packets received via radio to APRS-IS, allowing local stations to be viewed on the worldwide APRS network. Optional internet-to-RF forwarding features packet type selection, radius definition, security filters, and frequency limits. APRS Objects Register important points, such as shelters, support bases, aid posts, repeaters, obstacles, risk areas, or meeting places. Each object can contain a name, coordinates, symbol, and message, with publication via internet and/or RF. Mobile or Fixed Station Use dynamic location while on the move or configure fixed coordinates to operate as a base, iGate, Digipeater, or support station. Symbols and Status Messages Choose the APRS symbol representing your station, vehicle, or activity, and add a message to inform your condition or mission. Communication Monitoring Track sent and received packets in the integrated terminal, along with the status of the APRS-IS connection and RF operation. Automatic Reconnection After temporary internet interruptions, the app attempts to re-establish the connection with the APRS-IS server. USE CASES Tracking during trips, expeditions, and outdoor activities. Monitoring of vehicles and volunteer teams in the field. Support for search, rescue, civil defense, and humanitarian aid operations. Local APRS radio operation in areas without internet. Temporary installation of an iGate or Digipeater to expand coverage. Publishing shelters, bases, risks, and support points as APRS Objects. Technical monitoring of AX.25 packets and APRS-IS communication. SIMPLE AND CONFIGURABLE Enter your amateur radio callsign, Passcode, server, and transmission preferences to begin. RF, Digipeater, and iGate features are disabled by default and only work when enabled by the user. IMPORTANT REQUIREMENTS Access to APRS-IS requires an amateur radio callsign and a valid Passcode. RF operation requires a radio and a compatible audio interface. Performance depends on equipment, audio levels, VOX/PTT configuration, and channel conditions. Continuous use of GPS, audio, and background execution may increase battery consumption.