Open Your Windows vs Aerzeit

Fresh air, without the guesswork. Open Your Windows gives you one simple answer: is right now a good time to open the windows? Most days you want fresh air. But checking a weather app, an AQI app, and a pollen app to decide takes five minutes and three different recommendations. Too long if you'd like to check several times a day, and if it's important to you to get fresh air. This app looks at all of it — temperature, humidity, dewpoint, air quality, pollen, wind gusts, and rain forecasts — and gives you one clear recommendation with a plain-English reason. What you see — Open, Maybe, or Keep Closed. One answer, right now. — Plain-language reason ("It's a comfortable 72° and AQI is 42 — in the good range.") — Short-term outlook so you know how long conditions will hold. — Home screen widget in two sizes for glance-and-go checks. — Parameter detail when you want to see the why. — Pollen sensitivity toggle for allergy-prone households. How it decides It's not AI. It's a deterministic rule engine with thresholds tuned for real household comfort. Hard vetoes for unsafe air. Soft modifiers for things that affect how pleasant it'll feel. Short-term forecast awareness so you're not told to open right before a storm. Hysteresis so the answer doesn't flip every two minutes on borderline days. If conditions are genuinely borderline, it says Maybe and tells you why. If something upstream breaks or good weather data are not available, it says so instead of guessing. Trust comes from predictability. Privacy, seriously — No account. No login. No tracking. — Your location is used to fetch weather for your spot, then discarded. Never stored on our servers. — Analytics are anonymous. No device IDs. No IP addresses. No location. — API keys for weather, AQI, and pollen providers stay on our backend. Your phone never talks to them directly. Who it's for Anyone who loves fresh air and doesn't love checking three apps to decide. Parents of kids with allergies. People with asthma. Anyone who's opened the windows on a day the pollen count was secretly brutal and paid for it the next morning. Not a medical device. This is a household comfort tool, not allergy advice. If you have serious respiratory conditions, talk to your doctor — but let this app take "is today a good day?" off your list. Built in the spring in the Midwest by one person with allergies and asthma who wanted an app that just gives him the answer.

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 (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/