# iSailGPS : NOAA USA RNC Charts — Marine Nautical Chart Plotter > Marine nautical chart plotter with US NOAA raster charts for offline GPS navigation. (iPhone/iPad app by James Associates Inc..) - Source: https://appshunter.io/ios/app/isailgps-noaa-usa-rnc-charts/id433950540 (this page in markdown: same URL + `.md`) - Developer: [James Associates Inc.](https://appshunter.io/developer/351499178) - Category: Navigation, Travel - Price: $7.99 - Rating: 3.90/5 from 72 App Store ratings · 70 written reviews indexed - Age rating: 4+ - Requires: iOS 12.0 · 10 MB - Languages: American English - Released: 2011-04-29 - Data updated: 2026-09-03 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/isailgps-noaa-usa-rnc-charts/id433950540/reviews.md ## What is iSailGPS? Unleash the navigation potential of your iPhone or iPad with SailGPS! Turn your device into a high-performance GPS receiver with USA NOAA Raster Nautical Charts, even without a cell signal! Rated “Best Choice — Excellent” by Practical-Sailor.com Caught in a storm on the water and your chart plotter fails? Don't worry! Download this app now and regain full navigation capabilities to safely return to port. Better yet, buy iSailGPS today ensuring you're prepared for any situation, even in areas with no cell service. One Low Price! Everything included. No sign-ups, ads, subscriptions or in-app purchases. Completely respects your privacy. Unrivaled Features to Enhance Your Journey: TRACKS, WAYPOINTS & ROUTES Record tracks as you sail, even in the background. View them on the chart and in a Speed & Course Over Ground graph. Mark waypoints precisely using charts or satellite maps, place names or addresses, geotagged photos, or by projecting from a known point. Set a quick GoTo waypoint or a full route and see the course (COG), heading (HDG), bearing (BRG), direction, distance, cross track error (XTE), Velocity Made Good (VMG) and Estimated Time of Arrival (ETA) at your destination and intermediate points. Perfect for racing enthusiasts. In a Man Overboard (MOB) emergency a single button press marks your current position & starts navigating to it. Create customized routes using waypoints, recorded tracks, or imported GPX, KML or TCX files. Advanced route editing. Send GPX and KML waypoint, route, track and map list files via AirDrop, eMail, Messages, or iCloud Drive. View the sun & moon position and rise & set times for any date & place on earth. Send data to other apps such as Google Earth. USA NOAA RASTER NAUTICAL CHARTS Access to all NOAA RNC Charts for USA waters with no extra charge. Download using WiFi or cell service. Our chart files are optimized to download faster & use less storage memory. Store up to 2200 charts to use anytime at sea without cell service. Stitches charts & automatically switches between downloaded charts as you sail. Choose detailed or overview charts. Print & Share chart images overlaid with waypoints, routes & tracks. Measure distance & direction between any 2 points. NOAA charts don't include most inland rivers & small lakes. Use our iHikeGPS app for these. HOW TOS Tap Help in the app. Online Manual: isailgps.com Email developer: lwjames@isailgps.com RASTER CHARTS VS. VECTOR CHARTS The National Oceanic & Atmospheric Administration has provided both RNC (raster) & ENC (vector) charts. The great advantage of the high resolution RNC charts used by iSailGPS is the high level of detail produced by professional cartographers that is unobtainable on any vector-based chart. These RNC Charts differ from vector charts in that each chart covers a specific area, just as paper nautical charts do. Switches automatically to a new chart when your boat leaves the area covered by the previous chart. For most locations, there are multiple charts at different scales with different levels of detail & areas of coverage. Paper charts can have multiple panels, each showing a different area or scale. Each digital panel is individually displayed by iSailGPS with a north-up orientation. iSail GPS is priced to make it readily available to all boating enthusiasts. Winner of the Practical Sailor Editors’ Choice Award. DEVICE REQUIREMENTS Use iSailGPS on any iOS device even if you don't have a cellular data plan for it. iPhones & WiFi+cellular iPads support full navigation. For WiFi-only iPads & iPod touch, an iOS-compatible external GPS receiver is required to show your location on the water & record tracks. However, you can view charts using the iOS device alone. Discover a safer and more enjoyable sailing experience with iSailGPS! ## Key features - USA NOAA Raster Nautical Charts - Offline GPS navigation - Track recording and display - Waypoint and route creation - Man Overboard (MOB) function - GPX/KML file import/export - Sun & moon position tracking ## Chart rankings - #99 in Top Paid · Navigation (US App Store) ## What do users think of iSailGPS? Overall sentiment: mostly positive **Pros** - 👍 Great app for sailing - 🗺️ Accurate NOAA charts - 🚀 Fast and efficient - 💰 Excellent value for price - 🧭 Reliable GPS tracking - ✅ Simple and clear interface - 💡 Good for planning and backup - 🛠️ Excellent customer support - 🔋 Battery friendly (mentioned by one user) - 🔄 Seamless chart updates - 📱 Useful on iPhone/iPad - 🌟 Highly recommended by many - 🆓 Free chart downloads - 🛄 Easy waypoint and route creation - 📈 Accurate speed and course tracking - 🗄️ Good for storing routes/waypoints **Cons** - ⚠️ Chart management issues - ❌ Limited to NOAA charts (no international) - 🐌 Slow response when zooming/panning - 📉 Poor battery life (mentioned by one user) - 🚫 No auto-routing feature - 🗄️ Chart stitching problems - 🗺️ Charts can be blurry when zoomed - 🤔 Not intuitive for some users - 📍 Waypoint placement can be off - ❓ Difficulty finding specific charts - 🧭 Compass heading issues - 🎛️ Map rotation issues - 🚫 No inland water navigation markings - 🔠 Layout can be confusing - 📏 Not detailed enough for some - 🖨️ Limited export options - 🎛️ No course-up feature - 🛄 Chart download method is quirky - ⚠️ Can be a battery hog in track mode - ❌ Useless for Canadian waters (mentioned by multiple users) - ❌ Useless for some inland lakes - 🐛 App hangs up/crashes - ❌ Not suitable for advanced users seeking modern features **Commonly reported bugs** - HDG and COG issues - Compass heading is dangerous - Map compass locked, cannot be rotated - App hangs up during update - Updated app on iPad no longer works on iPhone - App crashes - Slow response when zooming/panning - Tracking line is hit-or-miss - Server problems when downloading charts - Unworkable map loading **Most requested features** - Ability to stitch charts seamlessly - Automatic chart detail selection - Disable compass heading - Course on ground always on and efficient - Download chart kits, not individual charts - Use current map focal point to load local chart - Add 'use map' to 'add waypoints' screen - Sort charts by number - Apple Watch app with basic stats - Float plan sending with waypoints - Export to a computer version - Set up borders on chart with vibration/tone - Download additional waypoint icons - Dark mode option - Instrument panel page with big numerals - More advanced charting capabilities (shading, safety zones, depth levels) - Show all NOAA charts in one color, downloaded charts in another ## Recent user reviews (10 of 70) All indexed reviews: https://appshunter.io/ios/app/isailgps-noaa-usa-rnc-charts/id433950540/reviews.md ### 5/5 — E Norm *2025-09-01* Great App! Had it about 6 years now and it’s awesome, nothing better available in its class! ### 3/5 — I like it! *2025-07-31* I Haven’t used it much but it just pleases me. High res Raster charts, to the point, fast, reminds me of GPSNavX that I still use today. Many thanks! Ok, problem with HDG and COG. Compass heading is terribly dangerous, we should be able to disable it. Course on ground should be always on and efficient. Down to three stars for me, sad! ### 5/5 — Simple accurate actual charts *2024-07-27* I miss charts. This is by far my favorite app for sailing. No distractions, just clear accurate markings on a proper chart! ### 5/5 — I like it! *2024-07-22, version 9.4.9* I Haven’t used it much but it just pleases me. High res Raster charts, to the point, fast, reminds me of GPSNavX that I still use today. Many thanks! ### 3/5 — Poor chart management *2024-03-26* The main problem for me is the inability to stitch together a see less chart and being able to get the best detail for the area automatically. I’ve been playing with app for awhile now and when I get to the chart boundary I can often get the next chart to show by double tapping the white area outside of it. And sometimes, I think, it seems to have successfully stitched together into a single, larger chart. But, it may not have the sufficient detail I need for a particular port. At that point I’m forced to go to my downloaded charts and find it. Not so simple as I now have a long list of charts. This can be impractical to do on the water unless you have a dedicated navigator. When approaching a busy area I don’t want to take my eyes off the water and be scrolling through a list of charts trying to find the appropriate detail. Maybe I’m missing something but for me other apps with paid subscriptions work a lot better. There’s just no chart management needed, and you can find them for as little as $5/year (at least for my area - eastern US coast). ### 5/5 — Finestkind! *2024-01-02, version 9.4.3* Tracking and data viewing and export are excellent. NOAA chart integration is perfect. Highly recommended. ### 5/5 — The Perfect Combo *2023-11-22* iSail is the perfect combination of gps tracking tech and time honored and trusted NOAA charts. Easy interface allows for quick waypoint and route creation, and accurate speed over ground, course over ground, and location tracking over time. Adding new charts and their upclose inserts from all over the US is quick and intuitive. Highly recommended for day sails and multi-waypoint long distance trips. ### 5/5 — Works great *2023-11-04, version 9.4.3* I have been using it for 8 years. Tracked to Bermuda BVI and Florida to Baltimore. Charts are free mine has no subscription ### 5/5 — Always Impressed *2023-05-22* After investing a little time to understand this app, I found it to be extremely valuable and accurate. I was won over, when we used it to navigate across the Chesapeake Bay at night. The waypoint marker we were heading to was supposed to be a flashing light but the light was out and we were a little uncertain that we were on course. When we suspected we should be at our destination marker we turned on our spot light and found ourselves perched with the marker on our port quarter. Can’t believe this app is only $7.99. ### 5/5 — Good simple program *2022-11-15* Have tried several programs - this program seems to be the most battery friendly and is a good backup program. Very stable. Main limitation seems to be the app only works w NOAA charts so no international use. ## Frequently asked questions about iSailGPS ### What does iSailGPS do? iSailGPS turns your iPhone or iPad into a high-performance GPS receiver using USA NOAA Raster Nautical Charts. It allows for offline navigation, tracking your journey, setting waypoints, creating routes, and provides essential navigation data like course, speed, and estimated time of arrival. ### What are the key features of iSailGPS? Key features include access to all USA NOAA RNC Charts for offline use, recording and displaying tracks, marking waypoints, creating and navigating routes, a Man Overboard (MOB) function, and the ability to import/export GPX and KML files. It also shows sun and moon positions. ### How much does iSailGPS cost? The app is available for a one-time low price, with everything included. There are no sign-ups, ads, subscriptions, or in-app purchases, ensuring your privacy is respected. ### Is iSailGPS compatible with my device? The application is designed for iPhone and iPad devices. Specific compatibility details, such as supported iOS versions, can typically be found on the app's store page. ### When would I use iSailGPS? You would use iSailGPS for marine navigation, especially in areas with no cell signal, during storms, or when a chart plotter fails. It's ideal for everyday sailing, racing, and ensuring safe return to port. ## Version history (last 5 releases) ### 9.6.9 — 2026-04-24 Improved wording on some Alerts and Notifications. What's new in iSailGPS when compared with other available NOAA chart apps? • You don't just see Waypoints and Routes displayed on the chart, you can actually do real great circle navigation to those Waypoints and along those Routes. You get information such as Estimated Time of Arrival, current bearing, heading and cross-track error, and remaining distances to your intermediate and final destinations. • You don't just see individual charts. Whenever the map projection is compatible (which it is most cases), you can see adjacent charts with their margins removed stitched together seamlessly, even when the chart scales are different. For example you can see the approach chart and the corresponding harbor detail chart both together on the same screen. • You can create, import, edit, export, and navigate both on routes based on a recorded or imported path, and on routes based on a series of waypoints. • Get the weather report and forecast, the sun and moon position, rise and set times, and driving directions to the dock for any point on a chart with a few taps. • iSailGPS's code size is kept very small by efficient programming so in an emergency, you can download it easily even over a weak cell connection. • The current version of iSailGPS runs on the latest devices and also on older devices with older versions of iOS , all the way back to devices such as the iPhone 6. • There is never any confusion over what charts you have available offline. They are clearly listed by NOAA chart name and number, and shown on an overview map. • Check the App Privacy section. We don't know who you are when you are using iSailGPS. We never send your current location or your recorded track to our servers. Hence we cannot and don't use your location data. We cannot and don't provide your location data to anyone else. Unlike other mapping apps that profit from using your location data in ways that do not keep it private, iSailGPS maintains the highest level of data confidentially. ### 9.6.6 — 2025-11-10 Updated for iOS 26.1. We're regularly improving this app so it will be even more useful! What's new in iSailGPS when compared with other available NOAA chart apps? • You don't just see Waypoints and Routes displayed on the chart, you can actually do real great circle navigation to those Waypoints and along those Routes. You get information such as Estimated Time of Arrival, current bearing, heading and cross-track error, and remaining distances to your intermediate and final destinations. • You don't just see individual charts. Whenever the map projection is compatible (which it is most cases), you can see adjacent charts with their margins removed stitched together seamlessly, even when the chart scales are different. For example you can see the approach chart and the corresponding harbor detail chart both together on the same screen. • You can create, import, edit, export, and navigate both on routes based on a recorded or imported path, and on routes based on a series of waypoints. • Get the weather report and forecast, the sun and moon position, rise and set times, and driving directions to the dock for any point on a chart with a few taps. • iSailGPS's code size is kept very small by efficient programming so in an emergency, you can download it easily even over a weak cell connection. • The current version of iSailGPS runs on the latest devices and also on older devices with older versions of iOS , all the way back to devices such as the iPhone 6. • There is never any confusion over what charts you have available offline. They are clearly listed by NOAA chart name and number, and shown on an overview map. • Check the App Privacy section. We don't know who you are when you are using iSailGPS. We never send your current location or your recorded track to our servers. Hence we cannot and don't use your location data. We cannot and don't provide your location data to anyone else. Unlike other mapping apps that profit from using your location data in ways that do not keep it private, iSailGPS maintains the highest level of data confidentially. ### 9.6.5 — 2025-09-04 User interface improvements. We're regularly improving this app so it will be even more useful! What's new in iSailGPS when compared with other available NOAA chart apps? • You don't just see Waypoints and Routes displayed on the chart, you can actually do real great circle navigation to those Waypoints and along those Routes. You get information such as Estimated Time of Arrival, current bearing, heading and cross-track error, and remaining distances to your intermediate and final destinations. • You don't just see individual charts. Whenever the map projection is compatible (which it is most cases), you can see adjacent charts with their margins removed stitched together seamlessly, even when the chart scales are different. For example you can see the approach chart and the corresponding harbor detail chart both together on the same screen. • You can create, import, edit, export, and navigate both on routes based on a recorded or imported path, and on routes based on a series of waypoints. • Get the weather report and forecast, the sun and moon position, rise and set times, and driving directions to the dock for any point on a chart with a few taps. • iSailGPS's code size is kept very small by efficient programming so in an emergency, you can download it easily even over a weak cell connection. • The current version of iSailGPS runs on the latest devices and also on older devices with older versions of iOS , all the way back to devices such as the iPhone 6. • There is never any confusion over what charts you have available offline. They are clearly listed by NOAA chart name and number, and shown on an overview map. • Check the App Privacy section. We don't know who you are when you are using iSailGPS. We never send your current location or your recorded track to our servers. Hence we cannot and don't use your location data. We cannot and don't provide your location data to anyone else. Unlike other mapping apps that profit from using your location data in ways that do not keep it private, iSailGPS maintains the highest level of data confidentially. ### 9.6.4 — 2025-07-18 Improved user interface uniformity with varying iPad screen sizes. We're regularly improving this app so it will be even more useful! What's new in iSailGPS when compared with other available NOAA chart apps? • You don't just see Waypoints and Routes displayed on the chart, you can actually do real great circle navigation to those Waypoints and along those Routes. You get information such as Estimated Time of Arrival, current bearing, heading and cross-track error, and remaining distances to your intermediate and final destinations. • You don't just see individual charts. Whenever the map projection is compatible (which it is most cases), you can see adjacent charts with their margins removed stitched together seamlessly, even when the chart scales are different. For example you can see the approach chart and the corresponding harbor detail chart both together on the same screen. • You can create, import, edit, export, and navigate both on routes based on a recorded or imported path, and on routes based on a series of waypoints. • Get the weather report and forecast, the sun and moon position, rise and set times, and driving directions to the dock for any point on a chart with a few taps. • iSailGPS's code size is kept very small by efficient programming so in an emergency, you can download it easily even over a weak cell connection. • The current version of iSailGPS runs on the latest devices and also on older devices with older versions of iOS , all the way back to devices such as the iPhone 6. • There is never any confusion over what charts you have available offline. They are clearly listed by NOAA chart name and number, and shown on an overview map. • Check the App Privacy section. We don't know who you are when you are using iSailGPS. We never send your current location or your recorded track to our servers. Hence we cannot and don't use your location data. We cannot and don't provide your location data to anyone else. Unlike other mapping apps that profit from using your location data in ways that do not keep it private, iSailGPS maintains the highest level of data confidentially. ### 9.6.3 — 2025-07-02 Improved user interface uniformity with varying screen sizes. We're regularly improving this app so it will be even more useful! What's new in iSailGPS when compared with other available NOAA chart apps? • You don't just see Waypoints and Routes displayed on the chart, you can actually do real great circle navigation to those Waypoints and along those Routes. You get information such as Estimated Time of Arrival, current bearing, heading and cross-track error, and remaining distances to your intermediate and final destinations. • You don't just see individual charts. Whenever the map projection is compatible (which it is most cases), you can see adjacent charts with their margins removed stitched together seamlessly, even when the chart scales are different. For example you can see the approach chart and the corresponding harbor detail chart both together on the same screen. • You can create, import, edit, export, and navigate both on routes based on a recorded or imported path, and on routes based on a series of waypoints. • Get the weather report and forecast, the sun and moon position, rise and set times, and driving directions to the dock for any point on a chart with a few taps. • iSailGPS's code size is kept very small by efficient programming so in an emergency, you can download it easily even over a weak cell connection. • The current version of iSailGPS runs on the latest devices and also on older devices with older versions of iOS , all the way back to devices such as the iPhone 6. • There is never any confusion over what charts you have available offline. They are clearly listed by NOAA chart name and number, and shown on an overview map. • Check the App Privacy section. We don't know who you are when you are using iSailGPS. We never send your current location or your recorded track to our servers. Hence we cannot and don't use your location data. We cannot and don't provide your location data to anyone else. Unlike other mapping apps that profit from using your location data in ways that do not keep it private, iSailGPS maintains the highest level of data confidentially. ## Apps similar to iSailGPS | App | Rating | Price | Category | | --- | --- | --- | --- | | [iNavX: Marine Navigation](https://appshunter.io/ios/app/inavx-marine-navigation/id286616280) | 4.8 (21,564) | Free | Navigation | | [i-Boating: Marine Charts & Gps](https://appshunter.io/ios/app/i-boating-marine-charts-and-gps/id994992062) | 4.5 (14,760) | Free | Navigation | | [PRO CHARTS - Marine Navigation](https://appshunter.io/ios/app/pro-charts-marine-navigation/id451093694) | 4.5 (8,499) | Free | Navigation | | [Wavve Boating: GPS, Map, Chart](https://appshunter.io/ios/app/wavve-boating-gps-map-chart/id1241140495) | 4.7 (6,278) | Free | Navigation | | [Aqua Map Boating](https://appshunter.io/ios/app/aqua-map-boating/id919552329) | 4.7 (13,587) | Free | Navigation | | [Nautical Charts & Maps](https://appshunter.io/ios/app/nautical-charts-and-maps/id1420774597) | 4.6 (3,780) | $8.99 | Navigation | ## More apps by James Associates Inc. - [iHikeGPS : Classic Topo Maps](https://appshunter.io/ios/app/ihikegps-classic-topo-maps/id351499175) - [iHikeGPS NZ : LINZ Topo Maps](https://appshunter.io/ios/app/ihikegps-nz-linz-topo-maps/id490570230) - [iSailGPS NZ : Nautical Charts](https://appshunter.io/ios/app/isailgps-nz-nautical-charts/id911580513) All apps by James Associates Inc.: https://appshunter.io/developer/351499178 ## Related topics [isailgps](https://appshunter.io/ios/topics/isailgps) · [chart plotter sailing](https://appshunter.io/ios/topics/chart-plotter-sailing) · [noaa charts navigation](https://appshunter.io/ios/topics/noaa-charts-navigation) · [isailor](https://appshunter.io/ios/topics/isailor) · [free marine charts](https://appshunter.io/ios/topics/free-marine-charts) --- *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 2026-09-03.*