Frequently asked questions about Là-haut

Yes: no ads, no subscription, no in-app purchase, no account. Forecasts come from Open-Meteo's free API, whose free tier is for non-commercial apps only — which is why Là-haut sells nothing.

For stars: clouds 60 % (low at 100 %, mid at 80 %, high at 40 %), moon 25 % (illumination × altitude), haze and humidity 10 %, wind 5 %, over the window from the end of civil twilight to three hours later. Sunset and moon have their own weights and windows. Caps stop dry air from making up for an overcast sky or a full moon. The app shows the breakdown of every score.

From Open-Meteo (open-meteo.com, CC BY 4.0), which provides hourly cloud cover by layer, visibility, humidity, wind and chance of rain. Sun, moon and twilights are computed on the phone.

It's an estimate. The app shows a confidence indicator: good for tonight and tomorrow, medium up to three days, low beyond, and lower still when clouds change a lot from hour to hour. Far-off evenings are flagged “uncertain”.

Because mid or high clouds (between 20 and 60 %) catch the colours — that's what makes spectacular sunsets. A bare sky gives a pretty but flat sunset, and low clouds block the horizon.

If you allow it, it's used at about 3 km accuracy, only to ask for the weather. You can also add places by hand (the garden, the country house, a dark site) without sharing your location.

Yes. Every 2 hours it downloads your place's forecast and recomputes the score with the same engine as the app. If that fails, it shows the last known score.

Not yet: the interface is in French for now.

iPhone on iOS 17 or later, with Home Screen and Lock Screen widgets.