NerdTrack vs VibraScope

NerdTrack records your location in a CSV file on your phone. No other data is collected and no data ever leaves your device. Full source is available at https://nerdtrack.org There is no interactive UI. Just grant location permissions, and it will log in the background. To stop logging, remove location permissions or uninstall app. The app uses the SignificantLocation and CLVisit APIs. The accuracy is low but it has very low battery usage. To get your log, open the Files app, and look for locations.csv in the Nerd Track folder. A config file will be created in the app's documents folder the first time it runs. Edit that file to change logging frequency or minimal distance. Force-stop and restart app to reload config. By default, the app records location: - Every 15 minutes, if you have moved more than 300 meters The CSV logs timestamps in the unix epoch format. Use 'dateconv -i %s' to convert it to something more human-readable. Some helper scripts are available at https://nerdtrack.org

VibraScope turns your phone into a vibration meter and seismograph — measure shaking, engines, appliances and floors with the motion sensor already in your pocket. It looks and feels like a classic paper chart recorder: a live analog needle gauge, three seismograph-style ink traces (X/Y/Z), and readouts stamped like an instrument plate. Warm paper theme by day, amber night-instrument theme in the dark. MEASURE WITHOUT INTERRUPTIONS • No full-screen ads on the measuring screen — your reading never gets wiped mid-measurement • Remove ads with a single one-time purchase, forever WHAT YOU GET • Live analog needle gauge with color-coded intensity zones • 3-axis seismograph traces or a single magnitude trace — your choice • RMS, peak and session-max acceleration in m/s² or g • Estimated shaking intensity (MMI scale, I–XII) • Dominant vibration frequency in Hz • Zero calibration and hold • Save measurements with title and notes, review them anytime • Export charts as images (high-resolution available) or data as CSV • Works on both phones and tablets • 8 languages Everything is measured and stored on your device — no account, no sign-up, and the motion sensor needs no permission at all. Great for checking washing machines and engines, monitoring workshop tools, testing floors and shelves, classroom physics, or simply seeing every little tremor around you drawn in ink. Note: readings are estimates from consumer phone sensors and do not replace calibrated instruments or official seismic monitoring.