Comparison

WatchBarometer vs Aerzeit

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

WatchBarometer

This app provides detailed air pressure data, weather trends, and altitude history for iPhone and Apple Watch. It offers insights into pressure changes and their relation to weather, with customizable widgets and complications.

Highlights
  • Current and sea-level pressure
  • Short-term weather trend analysis
  • Pressure history tracking
  • GPS altitude history
  • Widgets and Live Activity support
  • Apple Watch complications
Features
Read full description

WatchBarometer turns air pressure into useful context on iPhone and Apple Watch. Highlights: - current sensor pressure or sea-level-normalized pressure - short-term weather trend from pressure changes - pressure history from six hours to the complete timeline - comparison of raw and altitude-aware sea-level pressure - GPS altitude history with optional barometer refinement - focused measurement sessions - widgets, Live Activity, and Apple Watch complications WatchBarometer uses the device's running barometer stream, GPS altitude for sea-level context, and read-only HealthKit samples only when Apple already includes barometric pressure metadata. Important: - high- and low-pressure classifications use compensated sea-level pressure only - raw sensor pressure is not misleadingly classified across different elevations Built for weather watchers, hikers, and anyone who wants to understand pressure, trend, and altitude instead of seeing just one number. Privacy Policy: https://bernhardhering.de/privacy/ Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Aerzeit

This app analyzes local weather forecasts to suggest optimal times for opening windows to ventilate your home with fresh air. It allows customization of preferred temperature ranges and filters for rain, humidity, wind, air quality, and pollen.

Highlights
  • Optimal window opening times
  • Customizable temperature ranges
  • Rain, humidity, wind filters
  • Air quality and pollen alerts
  • 48-hour forecast chart
  • Apple Watch companion app
Features
Read full description

Aerzeit watches the next 48 hours and tells you the stretches when the air outside is in the temperature range you chose — so you know when it's worth opening up instead of leaving the system running. When nothing in the next two days is worth it, it says so. Everything else is yours to switch on: rain, humidity, wind, air quality, pollen, UV, sun position, and the hours you'd actually consider opening. Set it once for your climate and your house, wherever in the country you are. WHAT IT DOES Pick the outdoor temperature range you'd be happy to let in. Aerzeit watches the local forecast and tells you when conditions match — once a day, at a time you choose. It can also tell you the moment a window opens, and the moment to close it again. Turn on the filters that matter where you live: rain, humidity, wind, air quality, pollen, UV, and the hours of the day you'd actually consider opening up. Set a shortest and longest opening, so you don't hear about gaps too brief to use or leave one open longer than you meant to. A 48-hour chart shows every condition in one place, so you can see where they agree and where they don't. Tap "Use current location" to set a spot to roughly 1 km precision, or search for a town. A companion Apple Watch app and complication show the same at-a-glance status on your wrist, and keep themselves current even when your phone is elsewhere. A Home Screen widget shows the next open-window period at a glance. Aerzeit runs in 50 languages, picked on the Locations page beside °C/°F. WHAT IT DOESN'T DO Aerzeit doesn't model your home — it reports the outdoor conditions and leaves the judgement to you. Opening, sizing and timing the actual airing is yours. It reports public weather and environmental data (including air quality, pollen and UV) as a comfort tool, not medical advice; if a health condition makes any of those matter for you, follow your clinician's guidance. PRIVATE BY DESIGN - Empty Privacy Manifest. The app calls none of Apple's required-reason APIs. - No language detection. Aerzeit never reads your phone's language setting — that's one of the required-reason APIs it avoids — so you pick from 50 languages in the app instead. - Minimal data. To fetch a forecast, the app sends a roughly 7 km grid cell to Aerzeit's server — no account, no identifiers, no raw GPS, no history. Your temperature range and all your filter settings stay on your device. The data export (Settings → Export my data) shows exactly what's held — it's all on your phone. - No accounts. No analytics. No tracking. No advertising. No third-party SDKs beyond a small geospatial maths library. MADE INDEPENDENTLY Aerzeit is built and published by Samuel Harrold, based in Indianapolis, Indiana, USA. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

WatchBarometer4 screens
Aerzeit4 screens

Verdict

The call

The clearest difference is update cadence: Aerzeit at every 5 days against WatchBarometer's every 3 months. Aerzeit also leads on iOS requirement (16.4 vs 26.0). On price, rating, ratings volume and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. WatchBarometer sells 1 in-app purchase, starting at $3.99 per year and Aerzeit sells 1 in-app purchase, starting at $9.99 per year. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for WatchBarometer against 5.0 for Aerzeit. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

UpkeepUpdate frequency

WatchBarometer ships an update every 3 months, Aerzeit every 5 days. Both last shipped on October 28, 2026.

Scorecard2 real differences · 7 level
WatchBarometer versus Aerzeit: the parameters behind the verdict, then further details
ParameterWatchBarometerAerzeit
PriceFreeFree
Rating5.0 (1 ratings)5.0 (1 ratings)
Number of ratings11
Update frequencyEvery 3 monthsEvery 5 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFreemium
DevicesiPhone, Apple WatchiPhone, iPad, Apple Watch — better
Requires iOS26.016.4 — better
Further details — not scored
Size9 MB27 MB
Age rating4+4+
DeveloperBernhard HeringSamuel Harrold

In-app purchases

1 purchases

WatchBarometer

Subscriptions1
  • WatchBarometer Jahresabo$3.991 Year
1 purchases

Aerzeit

Subscriptions1
  • Aerzeit Premium$9.991 Year

Questions

Is WatchBarometer free?
WatchBarometer is free to download, with in-app purchases available.
Is Aerzeit free?
Aerzeit is free to download, with in-app purchases available.
Which has better reviews, WatchBarometer or Aerzeit?
WatchBarometer and Aerzeit are both rated 5.0 out of 5 on the App Store, from 1 and 1 ratings respectively.
Do WatchBarometer or Aerzeit have ads?
Neither WatchBarometer nor Aerzeit shows ads.
Which is updated more often, WatchBarometer or Aerzeit?
WatchBarometer ships an update every 3 months, and Aerzeit every 5 days. Most recently, WatchBarometer was updated on October 28, 2026 and Aerzeit on October 28, 2026.

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