APPLE WATCH · FREE · OFFLINE
Tideglass
A vintage marine instrument for your wrist. Next high, next low, anywhere on the coast.
Tideglass turns your Apple Watch into a vintage marine instrument for tide prediction. Open the app, see the next high and low for the spot you’re standing on, anywhere in the world — fully offline.
FEATURES
Mechanical-drum readout for the time and water level. Tick marks, vintage typography, no skeuomorphic clutter.
~8,000 tide stations bundled inside the app. No cell signal needed at the beach, no Wi-Fi on the boat.
Scrub forward and back through the day. Haptic ticks every 10 minutes so you can feel the curve.
High and low tides for the next several days, in the station’s local time, with magnitudes you can read at a glance.
ANYWHERE ON THE COAST
DATA, PROPERLY ATTRIBUTED
Tide harmonic constants come from the open OpenWaters tide database under CC BY 4.0. Upstream sources include NOAA (US public domain) and TICON-4 (CC BY 4.0). The prediction algorithm is adapted from Neaps (MIT).