iCaelumDifferent answers have different origins.
iCaelum calculates astronomical positions on the device and retrieves weather, air and tide data through its own service. The name of a source, its timestamps and its coverage matter as much as the number on screen.
Forecast providers
The forecast picker offers national services where available, Yr from MET Norway elsewhere, and alternative sources for comparison. Each service has its own forecast range and measurements.
Yr / MET Norway
The default national/global fallback forecast used where a more local national service is not selected.
Open-Meteo
An alternative forecast source and environmental data used by relevant tools.
OpenWeather is also listed separately in the app’s forecast sources.
Air, warnings, tides and maps
Official MeteoAlarm warnings describe the chosen place’s country and the warning’s own area and time. Air, pollen, tide and sea-state coverage varies; a missing value is not a reassuring zero.
Radar opens the selected provider’s own map. Wind maps have their own forecast hours and update behaviour. Lit-path tools use OpenStreetMap tags, which may not describe every light on a route.
Read the relevant view’s Sources and coverage notes for the feed used in that section. Observations, predictions, modelled conditions and calculated scores are not interchangeable.
On-device sky calculations
The Sun and Moon, shadows, light windows and Sky finder positions are calculated on the phone. Sky finder includes seven planets and an offline catalogue of 5,041 stars, with 330 named entries, based on the catalogue and naming sources documented in its guide.
Astronomical geometry does not detect clouds or obstacles. A marker above the horizon shows a calculated direction, not a promise that an object can be seen. A shadow model needs the dimensions and assumptions entered into that tool.
Sky finder’s camera supplies a background and device tracking; it does not recognise astronomical objects in photos. Camera images are not stored or transmitted.
What needs a connection?
On-device astronomical calculations and the bundled Sky finder catalogue do not need a forecast download. A usable position and functioning sensors are still needed for live instruments. Weather, environmental data, radar, map tiles and remote terrain or lighting data need a connection or available cached data.
The hiking SOS is a visual signal and coordinate display. It does not send an emergency message or make a call.
Forecast summaries and AI
A forecast’s written summary can come from its provider or be generated by AI from the available forecast. Check the labelled source and detailed measurements when timing matters. A summary is an interpretation of the underlying forecast, not a separate observation.