# iStreams Portland — Live and future tidal streams

> Offline Portland tidal stream atlas for navigation and passage planning. (iPhone/iPad app by Navtech Software.)

- Source: https://appshunter.io/ios/app/istreams-portland/id1455232883 (this page in markdown: same URL + `.md`)
- Developer: [Navtech Software](https://appshunter.io/developer/355517263)
- Category: Navigation, Utilities
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 18.6 · 38 MB
- Languages: American English, Danish, Dutch, French (France), German (Germany), Norwegian Bokmål
- Released: 2019-03-10
- Data updated: 2026-07-24
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/istreams-portland/id1455232883/reviews.md

## What is iStreams Portland?

iStreams gives you instant access to the Portland tidal stream atlas, aligned to the current time using High Water at Devonport — even when you're offline.

Whether you're sailing, navigating coastal waters, or passage planning, iStreams helps you understand tidal flow quickly and accurately.

Key Features:
Real-time tidal stream charts
Automatically displays the correct hourly chart based on the nearest Devonport High Water time.
Fully offline functionality  (forecast link requires a connection)
No signal? No problem. All charts and tools work without internet access.
Automatic chart updates
As time progresses, the app switches to the next valid tidal period.
Swipe forward and backward through tidal hours with ease.
Pinch to zoom and drag to explore details.
Toggle between Local Time and UTC.
Show boat position on the chart

Navigation Tools:
Interpolated Rate Calculator
    *  Instantly calculate stream rate between neaps and springs.
Tidal Set Tool (In-App Purchase)
     * Measure the true direction of tidal stream arrows with precision.
Course to Steer (CTS) (In-App Purchase)
     * Calculate the correct heading to maintain your intended course.

How It Works:
iStreams automatically selects the nearest High Water at Devonport and displays the corresponding tidal stream chart.

Want to plan ahead or review earlier conditions? Simply swipe forward or backward through the tidal hours to view past or future data.

Why Choose iStreams?
Designed for sailors, navigators, and coastal users
Fast, clear, and easy-to-use interface
Accurate tidal data when you need it most

## Key features

- Real-time tidal stream charts
- Offline functionality
- Automatic chart updates
- Swipeable tidal hours
- Interpolated Rate Calculator
- Tidal Set Tool (IAP)
- Course to Steer (IAP)

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Devonport Tides 2019 | $2.99 | one-time |
| 6 Month Subscription | $2.99 | one-time |
| 1 Month Subscription | $2.99 | one-time |
| 1 Year Subscription | $5.99 | one-time |
| Unlock 'Set' tool | $1.99 | one-time |
| Unlock CTS tool | $3.99 | one-time |


## Recent user reviews (1 of 1)

All indexed reviews: https://appshunter.io/ios/app/istreams-portland/id1455232883/reviews.md

### 5/5 — Excellent...

*2019-06-03*

....but you need to subscribe

**Developer response:** The app is free to download and try, using 2019 data. However if you subscribe, it will display 2020 ( or current year ) data.

## Frequently asked questions about iStreams Portland

### How does iStreams Portland get tidal data?

iStreams Portland uses High Water at Devonport to align its tidal stream atlas to the current time. It automatically selects the nearest High Water and displays the corresponding tidal stream chart.

### Can I use iStreams Portland without an internet connection?

Yes, iStreams Portland offers fully offline functionality for all charts and tools. You only need an internet connection for the forecast link.

### What navigation tools are available in iStreams Portland?

iStreams Portland includes an Interpolated Rate Calculator for stream rates between neaps and springs. The Tidal Set Tool and Course to Steer (CTS) are available as in-app purchases for more precise measurements.

### How often is iStreams Portland updated?

The app was last updated on May 31, 2026, with version 3.09. It automatically updates charts as time progresses to the next valid tidal period.

### What devices is iStreams Portland compatible with?

iStreams Portland is available for both iPhone and iPad devices.

### What is the age rating for iStreams Portland?

iStreams Portland has an age rating of 4+, making it suitable for a wide range of users.

### Does iStreams Portland have ads?

No, iStreams Portland does not contain advertisements. It is free to download and use, with optional in-app purchases for advanced tools.

### How do I navigate through tidal hours in iStreams Portland?

You can easily swipe forward and backward through tidal hours to view past or future data. The app also allows you to toggle between Local Time and UTC.

## Version history (last 5 releases)

### 3.10 — 2026-07-23

Localisations and minor bug fixes

### 3.09 — 2026-05-31

Chart data card now draggable to preferred position
Fix for malformed text when user has set large font for device

### 3.07 — 2026-05-27

Improved performance
Updated user interface
bug fixes

### 3.06 — 2026-05-23

Improved performance
Updated user interface

### 3.05 — 2026-05-19

Improved performance
Updated user interface

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## More apps by Navtech Software

- [E6b Pilot](https://appshunter.io/ios/app/e6b-pilot/id368495864)
- [iPlotter Solent](https://appshunter.io/ios/app/iplotter-solent/id397677340)
- [Dutchman's Log](https://appshunter.io/ios/app/dutchmans-log/id474782184)
- [iHeatLoss](https://appshunter.io/ios/app/iheatloss/id680564773)
- [Easter Match Puzzle](https://appshunter.io/ios/app/easter-match-puzzle/id836681161)
- [iStreams Channel Islands](https://appshunter.io/ios/app/istreams-channel-islands/id1223503159)

All apps by Navtech Software: https://appshunter.io/developer/355517263

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*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 2026-07-24.*