Gnomon is a personal light-planning utility for iPhone and iPad, provided as-is for your own use.
Sun and moon times computed from standard published astronomical algorithms (NOAA / Meeus). Values match almanac references within documented tolerances (about two minutes for sun events at ordinary latitudes; wider near the poles). Gnomon shows no forecasts and makes no claims about weather, visibility, or safety — do not use it as the sole basis for safety-critical decisions.
Gnomon Pro is offered as an auto-renewing monthly or annual subscription and a one-time Lifetime purchase, billed through your Apple ID. Subscriptions renew unless cancelled at least 24 hours before the period ends; manage them in Settings → Apple ID → Subscriptions. The free tier remains functional regardless of any purchase.
Spots you save are yours and stay on your device. Gnomon claims no rights over them.