Marine Barometer

Classic-style Barometer and Altimeter for Android

Welcome

Marine Barometer turns an Android phone with a built-in pressure sensor into a simple, readable weather instrument. It combines a sea-level-corrected barometer, an aircraft-style altimeter, and a reference needle so you can mark the current pressure and watch it rise or fall over time.

Current Version: 1.1.9 beta (update as needed)

Highlights

• Live barometer: Sea-level corrected pressure shown in hPa or inHg
• Altimeter: Aircraft-style three-pointer display with adjustable setting
• Reference needle: Mark the current pressure and watch the trend
• Pressure-sensor calibration: Corrects for phone sensor offset using a known elevation and known local pressure
• Simple controls: MENU, UNITS, SET, and center reset knob on the barometer
• Works offline after setup: Once calibrated, no internet connection is needed for ordinary use

Marine Barometer is part of the Virtual Cockpit family, but it is also useful on its own at home, on a boat, in an RV, or while travelling.

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Download

Current Version: 1.1.9 beta

Click the icon below to download the APK installation file:

Installation Steps

1. Tap the download link above.
2. Open your Downloads folder and tap the APK file.
3. If prompted, allow installation from unknown sources.
4. Let Google Play Protect scan the file.
5. Follow the prompts to complete installation.

Important: This app needs a phone or tablet with a built-in barometric pressure sensor. Many modern Android devices have one, but not all do.

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Screens

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Instructions

Quick Start

1. Install the app and allow any requested sensor permissions.
2. Find the elevation of your home, marina, campsite, or other reference location.
3. Look up the current local sea-level pressure from a reliable nearby weather report.
4. Open MENU → CALIBRATE and enter the known elevation and known pressure.
5. Set the altimeter to the same pressure if you want the indicated altitude to match your location.

Everyday Use

• Barometer dial: Shows the current sea-level corrected pressure.
• Reference needle: Press the barometer center knob to park the reference needle at the current reading. Later, compare the live needle against the reference needle to see whether pressure has risen or fallen.
• Altimeter dial: Shows indicated altitude based on the current barometric setting.
• UNITS button: Switches between hPa and inHg.
• SET button: Opens the pressure-setting entry for the altimeter.

A Practical Routine

1. In the morning, reset the reference needle to the current pressure.
2. Check the app again a few hours later.
3. If the live needle is above the reference needle, pressure has risen.
4. If the live needle is below the reference needle, pressure has fallen.

Notes

• Calibration removes sensor offset. It does not turn a phone into a laboratory instrument.
• Room temperature, sunlight on the phone, and abrupt movement can cause small short-term changes.
• For best results, calibrate where you know both the elevation and the current local pressure.
• Changing the altimeter setting should affect the altimeter only, not the barometer reading.

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Theory

What the pressure sensor measures
Your phone's pressure sensor measures the air pressure where the phone is sitting. That is local station pressure, not sea-level pressure.

Why elevation matters
Air pressure decreases with height. To compare pressure at different places, weather services correct local pressure to sea-level pressure. Marine Barometer does the same thing after you tell it the elevation of your location.

What calibration does
Calibration estimates the pressure-sensor error and stores a correction offset. After calibration, the app uses the corrected pressure plus the known reference elevation to compute the live barometer reading.

What the altimeter does
The altimeter does not know your true altitude by magic. It converts pressure into indicated altitude using the barometric setting you enter. If that setting is wrong, the indicated altitude will be wrong too.

What the reference needle does
The reference needle is a trend marker. It does not affect the measurement. It simply remembers an older pressure so you can compare then versus now at a glance.

Reading the trend
A rising barometer often goes with improving weather. A falling barometer often goes with unsettled weather. The size and speed of the change matter, and local geography still matters, so treat the app as one useful clue, not the whole forecast.

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Finding Your Elevation

To calibrate properly, you need the elevation of the place where the phone is sitting.

Recommended Sources

• Canada: NRCan Toporama — good for Canadian users and official mapping.
• Worldwide quick lookup: Free Map Tools Elevation Finder — simple click-on-map tool with latitude, longitude, and current-location options.
• Also useful: topographic-map.com (Canada)
• US mirror: topographic-map.com (US English)

Using topographic-map.com

• Type a place name in the search box, or use the geolocate button near the search bar.
• Zoom in until the pointer is over your home, dock, campsite, or launch point.
• Use the elevation at that spot as your reference elevation.

Example link to Calgary Airport (YYC)

Click on the link below for an example based on the instructions above for topographic-map.com

Calgary Airport (YYC) Elevation

The easiest way to make one is to open a nearby place once in the browser, then edit the center, zoom, and popup values in the address bar.

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History

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