GnssLogger App

Developed with Google

About this app

GnssLogger by Google enables in-depth analysis and logging of all types of location and sensor data such as GPS (Global Positioning System), network location and other sensor data. GnssLogger is available for phones and watches. It comes with the following features for phones:

HOME TAB:
● Control various data logging such as raw GNSS measurements, GnssStatus, NMEA, navigation messages, sensor data and RINEX logs.

LOG TAB:
● View all location and raw measurement data.
● Control offline logging using 'Start Log', 'Stop & Send' and 'Timed Log'.
● Enable specific items to be logged using corresponding switches in Home Tab.
● Delete existing log files from disk.

MAP TAB:
● Visualize on GoogleMap, the location provided by GPS chipset, Network Location Provider (NLP), Fused Location Provider (FLP), and computed Weighted Least Square (WLS) position.
● Toggle between different map views and location types.

PLOTS TAB:
● Visualize CN0 (Signal Strength), PR (pseudorange) Residual and PRR (pseudorange rate) Residual vs time.

STATUS TAB:
● View detailed information of all visible GNSS (Global Navigation Satellite System) satellites such as GPS, Beidou (BDS), QZSS, GAL (Galileo), GLO (GLONASS) and IRNSS.

SKYPLOT TAB:
● Visualize the data of all visible GNSS satellites using a skyplot.
● View the average CN0 of all the satellites in view and the ones used in fix.

AGNSS TAB:
● Experiment with Assisted-GNSS functionalities.

WLS Analysis TAB:
● View the Weighted Least Square position, velocity and their uncertainties computed based on raw GNSS measurements.
● Compare the WLS results to the GNSS chipset reported values.

It comes with the following features for watches running Wear OS 3.0 and higher:

● View real-time GNSS chipset status information.
● Log various GNSS and sensor data to CSV and RINEX files.

Ratings and reviews

It's a real PITA to get the data into Google Earth. To process the RINEX output get RTKLIB_EX_2.5.0 and mostly use the command-line options as the GUI versions are ROUGH. edit: crashes consistently when saving and sending logs. aagh!!!

Incredibly feature-rich app in an incredibly small package. VERY accurate GPS positioning, altitude and compass! I just wish my Google Pixel 9 Pro XL could use its engine for storing picture GPS location instead of the camera's built-in engine, which is extremely inaccurate (it wanders all over the place and can be off by hundreds of feet even outside)

Good app! But I have a question, why is there a difference between weighted least squares solution and GPS provider? Whereas GPS system uses WLS. Maybe there are corrections (using sensors and Wi-Fi for example) but in this case, what is the difference between fused location and GPS provider? Thanks

What’s new

• Share data for AI analysis - Tap on the new "Share" button to send yourself data files optimized for analysis by Gemini!
• Satellite PVT - Satellite PVT is now logged along with raw measurements.
• NavIC support - On Plots and Spoof/Jam tabs.