Torr: Barometer Altimeter4.2.0 - App Store

Free barometer & altimeter - real-time pressure, altitude, 10-day forecasts with migraine alerts, automatic history logging, and CSV export all in one app.

The dashboard displays high-precision real-time measurement data, offering peace of mind for mountaineering enthusiasts and outdoor adventurers.
It uses your device's built-in barometric pressure sensor, motion sensor, and GPS, allowing offline use.
It also features real-time trend graphs, making it ideal for observing short-term changes during typhoon approaches, sudden downpours, stair/elevator ascents/descents, or driving uphill.
The altimeter lets you simultaneously view readings from three sources-sensor, GPS, and QNH (sea-level corrected pressure)-plus a calibrated value matched to a known elevation such as a trailhead.
Each altitude is displayed visually on an arch gauge, and you can tap each source to learn about its characteristics and accuracy.
Since barometric pressure and altitude support various units, it can also be used for professional purposes by researchers and academic institutions.

Additionally, for those sensitive to weather changes and suffering from migraines or weather-related illnesses, it provides graphs forecasting barometric pressure and weather for the next 10 days, along with headache alert information based on published research, updated every 6 hours.
Its graphical, intuitive UI runs smoothly, making it a valuable tool for daily prevention and countermeasures.

Furthermore, measured barometric pressure data is automatically stored within the app.
It features a background measurement mode that enables measurements even when the app is in the background or asleep. You can view accumulated data and export it to CSV files.
It also supports Live Activities in the background, allowing you to view real-time data on Dynamic Island or the lock screen.

Beyond the main app, it also works with Apple Watch, letting you instantly check barometric pressure and altitude.

An all-in-one, high-performance barometer app covering all present, future, and past information related to barometric pressure.

The one-of-a-kind app you never knew you needed-that's "Torr"!!

【Features】
・Dashboard
　・Barometer (Atmospheric pressure data via pressure sensor)
　・Altimeter - View altitudes from 4 sources on arch gauges
　　・Sensor Altitude (absolute altitude from the barometric sensor)
　　・GPS Altitude (elevation above sea level via satellite positioning)
　　・QNH Altitude (sea-level corrected barometric altitude)
　　・Calibrated Altitude (calibration matched to a known elevation)
・Pressure Forecast
　・Up to 10 days of nearby sea-level pressure values and weather forecasts
　・Pressure graph showing trends like rises and falls
　・6-hourly migraine/weather sensitivity alerts based on published research
・History
　・Automatic data logging
　・Daily history export to CSV files
　・Background measurement mode
・Unit settings - 7 pressure units including Torr, hPa, kPa, mBar, psi, inHg, mmHg
・Color theme settings
・Daily pressure forecast notification
・Torr Pro - full 10-day forecast anytime, 30 days of past pressure, pressure alerts, graph widgets, ad-free
・Apple Watch compatibility and complication
・Home Screen and Lock Screen widgets
・Live Activity

【Other】
Some devices may not have a barometric pressure sensor or motion sensor.
Please note that in such cases, certain dashboard features may not be available.
Location access and an internet connection are required to use the barometric pressure forecast.
Location access is required for background measurement.

Please submit requests or inquiries via reviews or the support URL.

Version History - Now supports iPhone Duo
- The dashboard and History are easier to read on iPad and other large screens 4.2.0 1d ago - Minor fixes and improvements 4.1.2 Oct 6 - Minor fixes and improvements 4.1.1 Oct 3 - Optimized how alerts are determined in the Pressure Forecast
- Tap the panels at the top of the Pressure Forecast to see more details 4.1.0 Oct 2 - Major new features and improvements
- Get pressure changes delivered by push notification
- New Home Screen widgets
- No more full-screen ad when opening the Forecast tab. Watch an ad only when you want to unlock the 10-day forecast
- See past pressure forecasts up to 24 hours back
- Pro users can look back up to 30 days of past pressure forecasts
- Apple Watch complication for Pro users 4.0.0 Sep 29 - Fixed a bug where barometric pressure and relative altitude could stop being displayed under certain conditions 3.10.3 Apr 7 - Fixed a bug where the pressure forecast caution trend might not display when using the widget 3.10.2 Apr 6 - Improved accuracy of QNH altitude calculation
- Minor bug fixes and improvements to usability and stability 3.10.1 Mar 30 - Major altimeter redesign — view 4 sources (Sensor, GPS, QNH, Calibrated) on arch gauges
- Added altitude calibration feature
- Added "torr" as a pressure unit
- Minor bug fixes and improvements to usability and stability 3.10.0 Mar 29 - Bug fixes and usability and stability improvements 3.9.2 Mar 25 - Bug fixes and usability and stability improvements 3.9.1 Mar 22 - Added an interactive pressure chart to the history detail screen showing daily transitions
- Bug fixes and usability and stability improvements 3.9.0 Mar 19 - Bug fixes and usability and stability improvements 3.8.1 Mar 15 - Added setting to adjust auto-logging interval
- Added new color themes
- Bug fixes and usability and stability improvements 3.8.0 Mar 3 - Improved stability and fixed minor issues 3.7.1 10/01/2025 - Support new OS and new design
- Add subscription "Pro" plan with ad-free
- More limited features coming soon...
- Fix minor issues 3.7.0 09/12/2025 - New design of the Barometric Pressure Forecast
- Headache warning information in the Barometric Pressure Forecast is now easier to read
- Weather information has been added to the pressure forecast.
- Fixed minor bugs 3.6.0 07/21/2025 - Fixed minor bugs
- Improved stability 3.5.0 07/17/2025 - barometric pressure is now available in the background via Live Activities
- fixed an issue which App and Watch App settings were not synchronized
- please try with both running
- improve stability and fixed tiny bugs 3.4.0 04/07/2025 - Supports iOS 18 3.3.0 09/17/2024 Improved stability and fixed minor bugs 3.2.0 08/26/2024 - New design for watchOS 10
- Removed settings from watchOS app
- Settings in the main app are automatically reflected 3.1.0 01/04/2024 - jump to the current date/time by tapping the date/time panel in the pressure forecast
- minor bug fixes and stability improvements 3.0.1 12/30/2023 - Added barometric pressure forecast tab
- New color theme applied
- Old themes are still available in settings
- Support level upped to iOS 16, watchOS 9 and above
- Minor fixes and stability improvements 3.0.0 12/27/2023 - support inHg and mmHg pressure units
- use monospaced font for values on dashboard
- improve stabilities and user experiences
- fix minor bugs 2.6.0 12/11/2023