# Tidekeeper: Tides & Alerts — Offline tide charts, favorites > Offline tide predictions and alerts for US coastal stations. (iPhone/iPad app by Luke Bradford.) - Source: https://appshunter.io/ios/app/tidekeeper-tides-and-alerts/id6784364416 (this page in markdown: same URL + `.md`) - Developer: [Luke Bradford](https://appshunter.io/developer/326971268) - Category: Weather, Navigation - Price: Free with in-app purchases - Rating: 5.00/5 from 1 App Store ratings · 1 written reviews indexed - Age rating: 4+ - Requires: iOS 17.0 · 2 MB - Languages: American English - Released: 2026-07-01 - Data updated: 2026-08-26 - Monetization: free with in-app purchases - User reviews in markdown: https://appshunter.io/ios/app/tidekeeper-tides-and-alerts/id6784364416/reviews.md ## What is Tidekeeper? Tidekeeper gives you fast, dependable tide predictions for 1,200+ US coastal stations — and it works completely offline. Tide heights are computed right on your iPhone from official NOAA harmonic data, so you get the full curve and the next high and low even with no signal at the coast. Built around the things other tide apps get wrong: FAVORITES, FRONT AND CENTER Pin the spots you actually care about — your home break, the boat ramp, the fishing flat — and see all of them at a glance with the current height, whether the tide is rising or falling, and the next high/low with a live countdown. ALERTS THAT ACTUALLY FIRE Set high- and/or low-tide notifications and choose how far ahead to be warned (at the tide, or 15–120 minutes before). Because tides are predictable, Tidekeeper schedules them with the system — so they arrive on time even when the app is closed and your phone is offline. TRULY OFFLINE Everything is on-device: no network call, no backend, no API keys. Predictions keep working in a cove, on the water, or in airplane mode. A CLEAN, READABLE CHART See the day's tide curve with every high and low marked and a "now" line, plus a simple high/low table. Times are shown in the station's local time. YOUR PREFERENCES STICK Choose feet or meters and 12- or 24-hour time. Set it once; it stays that way. NO ACCOUNT. NO ADS. NO TRACKING. Tidekeeper doesn't ask you to sign in, doesn't show ads, and doesn't collect your data. ABOUT THE DATA Predictions are derived from NOAA CO-OPS published harmonic constants (public domain) and are referenced to Mean Lower Low Water (MLLW), the standard chart datum. They match NOAA's official predictions closely for planning purposes. NOT FOR NAVIGATION Tidekeeper is for planning and recreation. Do not use it as your sole tool for navigation or life-safety decisions; consult official sources and local conditions. TIDEKEEPER PRO Tidekeeper is free to use for your first favorites and their alerts. Upgrade to Pro for unlimited favorite stations, alerts on as many stations as you like, and the extended forecast — a single one-time purchase, no subscription required. Questions or a station you'd like added? We'd love to hear from you. ## Key features - Offline tide predictions - 1,200+ US coastal stations - Customizable favorite locations - High/low tide alerts - Live countdowns - Clean tide charts ## Pricing and in-app purchases Base price: Free. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Tidekeeper Pro | $4.99 | one-time | ## Recent user reviews (1 of 1) All indexed reviews: https://appshunter.io/ios/app/tidekeeper-tides-and-alerts/id6784364416/reviews.md ### 5/5 — Fully offline *2026-07-03* Great for alerts with no signal ## Frequently asked questions about Tidekeeper ### Does Tidekeeper have ads? No, Tidekeeper is completely ad-free. The developer explicitly states 'NO ADS' and 'NO TRACKING' in the app description. ### How accurate are Tidekeeper's predictions? Tidekeeper's predictions are derived from official NOAA CO-OPS published harmonic constants and are referenced to Mean Lower Low Water (MLLW). They closely match NOAA's official predictions for planning purposes. ### Can I use Tidekeeper without an internet connection? Yes, Tidekeeper is designed to work completely offline. All tide height computations are done on-device, ensuring functionality even in areas with no signal. ### What is the cost of Tidekeeper Pro? Tidekeeper Pro is available as a one-time purchase, with no subscription required. This unlocks unlimited favorite stations, alerts on as many stations as you like, and the extended forecast. ### What age rating does Tidekeeper have? Tidekeeper has an age rating of 4+. This indicates it is suitable for children and general audiences. ### How often is Tidekeeper updated? The latest version of Tidekeeper was released on July 2, 2026, indicating recent development activity. The app was initially released on July 1, 2026. ### What devices does Tidekeeper support? Tidekeeper is currently supported on iPhone devices. It is not specified if it is available for iPad or other Apple devices. ### Is Tidekeeper suitable for navigation? No, Tidekeeper is intended for planning and recreation only. It should not be used as the sole tool for navigation or life-safety decisions; always consult official sources and local conditions. ## Version history (last 2 releases) ### 1.1 — 2026-07-05 Bug fixes and improvements ### 1.0 — 2026-07-02 No release notes. ## More apps by Luke Bradford - [Symmetry Lab Classic](https://appshunter.io/ios/app/symmetry-lab-classic/id327084012) - [Symmetry Lab: kaleidoscope art](https://appshunter.io/ios/app/symmetry-lab-kaleidoscope-art/id327084738) - [THF Haiku](https://appshunter.io/ios/app/thf-haiku/id453464896) - [Textile: minimal notes](https://appshunter.io/ios/app/textile-minimal-notes/id1304075165) - [Treasure: Have more.](https://appshunter.io/ios/app/treasure-have-more/id1488834263) - [Treasure Basic](https://appshunter.io/ios/app/treasure-basic/id1562568808) All apps by Luke Bradford: https://appshunter.io/developer/326971268 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-26.*