panic‑kit®

01 · Apple Watch · Free · Offline

Tide­glass.

A vintage marine instrument for your wrist. Next high, next low, anywhere on the coast.

~8,000 tide stations 0 KB/day internet 0 accounts & ads
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Tideglass on Apple Watch — tide chart for Cascais, Portugal
Cascais, Portugal

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

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Brass-and-navy chronometer

Mechanical-drum readout for the time and water level. Tick marks, vintage typography, no skeuomorphic clutter.

Works without internet

~8,000 tide stations bundled inside the app. No cell signal needed at the beach, no Wi-Fi on the boat.

Draggable 24-hour chart

Scrub forward and back through the day. Haptic ticks every 10 minutes so you can feel the curve.

Multi-day forecast

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

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Tideglass — San Francisco
San Francisco
Tideglass — Cascais, Portugal
Cascais
Tideglass — Sydney
Sydney

Data, properly attributed

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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).

⚠ Recreational use only

Tide predictions are not for marine navigation. For safety-critical decisions, consult official publications from your national hydrographic office.