Cövek

Cövek – an indispensable tool for field surveyors and land surveyors. The application allows you to perform RTK-accurate GPS measurements directly from your Android device, with real-time coordinate transformation, vector geometry editing and shapefile export.

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### 🛰️ Connectivity

The application supports several connection methods for external GNSS receivers:

- USB (OTG) – Direct connection via USB-to-serial converter, with all major chipsets (CP210x, FTDI, CH340, etc.)
- Bluetooth (Classic SPP) – Connect a paired Bluetooth GPS/GNSS receiver wirelessly
- TCP Client – Access a network GNSS streamer (e.g. a server running on a local network)
- TCP Server – Publish NMEA data received by the device to other applications on the network

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### 📡 NTRIP – Real-Time RTK Correction

Built-in NTRIP Client to receive RTK (Real-Time Kinematic) correction data:
- Optional NTRIP Caster server and Mountpoint configuration
- Username/password based authentication
- Automatic GGA return to activate correction stream
- Real-time connection status and received data volume display

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### 🗺️ Coordinate systems and transformation

- ETRF2000 Real-time display of GPS coordinates
- EOV (EPSG:23700) – Hungarian Unified National Projection System automatic transformation, based on the official HD72→EOV grid (.gsb) file
- Accuracy at the level of 1 cm with HD72 grid correction

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### ✏️ Editing and measuring options

Full-fledged geometry editing is available on the OpenLayers-based map view:

- Point capture – from GPS position (RTK, device GPS, screen center) or manually with EOV coordinates
- Line drawing – Add, move, delete vertices
- Polygon editing – Define and modify closed areas
- Line distance measurement – Automatic distance display between points and along segments with cm/m accuracy
- Line extension – Extend selected segment to specified value in both directions
- Corner point actions: move, delete, copy coordinate

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### 📂 File management – ​​SHP, KML, ZIP

- Shapefile (.shp/.zip) loading and exporting – ESRI ArcGIS compatible format
- KML import (Google Earth format)
- Save / Save as to Android document library or any folder
- Automatic saving of work session when closing the application

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### 📏 Technical data

| Feature | Value |
|---|---|
| Min. Android version | Android 10 (API 29) |
| Target platform | Android 14+ (API 36) |
| GPS source | USB OTG, Bluetooth SPP, TCP |
| Coordinate system | ETRF2000 → EOV (HD72 grid) |
| File formats | SHP, KML, ZIP |
| NTRIP protocol | NTRIP 1.0 / 2.0 |
| Map viewer | OpenLayers 8 |

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### 🔒 Permissions

The application only requests the permissions that are absolutely necessary for its operation:
- Location – for NTRIP GGA return and use of device GPS
- Bluetooth – for connecting an external GNSS receiver (optional)
- Internet – for accessing the NTRIP server and the online basemap
- Notifications – to indicate that a background service is running

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Stakes – Measure accurately, edit quickly, export in a standard way.