iSailGPS Downloads & RevenueiSailGPS : NOAA USA RNC Charts · App Store
iSailGPS : NOAA USA RNC Charts is #191 in Navigation Paid in South Korea and charting in 6 of 30 countries we track.
Updated 11 Nov 2026 · rankings refresh through the day
DeveloperJames Associates Inc.
CategoryNavigation
Price7.99 USD
Released
Rating★ 3.9 (72)
Version9.6.9
Age rating4+
First seen by us
25 Sep 2026
25 Sep 2026Installs (est.)5k+ worldwide
iSailGPS : NOAA USA RNC Charts update history & changes
Last change · 5 events since 29 Apr 2011Full timeline ↓📈Charting in a new country📈Charting in a new country🆕First spotted by AppInsider📦Version 9.6.9🆕Released on the App Store
Full timeline · 5 events
- 📈iSailGPS : NOAA USA RNC Charts charting in a new countryAustralia
- 📈iSailGPS : NOAA USA RNC Charts charting in a new countryIndia
- 🆕iSailGPS : NOAA USA RNC Charts first spotted by AppInsider#40 in Top Paid · Navigation · United States
- 📦iSailGPS : NOAA USA RNC Charts version 9.6.9Improved 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.… more - 🆕iSailGPS : NOAA USA RNC Charts released on the App Store
Collected from the stores by AppInsider since we first spotted the app. Dates are when we saw each change.
Rating
3.9 ★
72 ratings
Measured
Best rank now
#191
Navigation PaidMeasured
iSailGPS : NOAA USA RNC Charts on the App Store
App details
App ID
433950540
Publisher
James Associates Inc.
On the store since
Apr 2011
15 years on the store
Minimum OS
iOS 12.0+
iPhone 5s and later
Devices
iPhone · iPad
Universal purchase
Content rating
4+
Languages
1
EN
Size
11 MB
Also listed in
Travel
iSailGPS : NOAA USA RNC Charts downloads
Worldwide, per day, and installs to date. The band is open; the exact number is free with an account.
How this is calculated
Apple publishes no download counts. App Store downloads come from chart positions and daily rating growth per country, calibrated on Google Play install counts; lifetime installs from ratings worldwide × installs per rating. Confidence is the chance the real number is within half to double ours.
Active users
All platforms, worldwide. Free with an account.
Stickiness (DAU / MAU)
how many monthly users open it on a given day
How this is calculated
Monthly users come from lifetime installs across every store, fitted on monthly active user figures companies publish; daily users = monthly × the typical daily/monthly ratio for the category. Confidence is the chance the real number is within half to double ours.
Where it ranks now
Every top chart it appears in across 30 countries.
| Country | Charts | Rank |
|---|---|---|
| South Korea | NavigationPaid | #191 |
 Canada | NavigationPaid | #133 |
 Brazil | NavigationPaid | #172 |
 India | NavigationPaid | #187 |
 Indonesia | NavigationPaid | #138 |
 United Arab Emirates | NavigationPaid | #148 |
Apps near iSailGPS : NOAA USA RNC Charts on the chart
Navigation Paid, around #191.
Ratings
App Store, worldwide.
Rating
3.9 ★
72 ratings
Measured
Ratings
72
Measured
Review momentum
ⓘ How we measure thisNew ratings a week
under 1
4-week average
Lifetime rating
3.8★
recent stars not readable yet: new ratings are a tiny share of the total
Review momentum
20/100
faster than 0% of Navigation apps
Review momentum (0-100) blends how fast the app collects ratings compared with other apps in its category (60%), whether that pace is speeding up (25%) and what recent raters give it (15%; recent stars well below lifetime pull it down). Ratings counts are read daily. A jump usually means a launch, a feature, ads or a new review prompt.
What users say about iSailGPS : NOAA USA RNC Charts
From the 50 most recent App Store reviews in the US.
Mixed but leaning positive (72% of recent reviews give 4–5 stars). People like it for being easy to use, and being useful. The main complaints are about price and subscriptions, and crashes and bugs.
What people like
- Ease of use: “Simple accurate actual charts”
- Useful: “Ability to sort charts by number would be helpful”
- Price & subscription: “Great value for the price”
- Design: “I have settled on this beautiful app as my favorite”
Common complaints
- Price & subscription: “There are no maps for the Tennessee River, I want my money back”
- Crashes & bugs: “With all that said, I still keep this app as my backup in case for some reason my Simrad app crashes along with my chartplotter”
- Speed & performance: “Unworkable map loading even on wifi!”
- Updates: “Excellent customer support, excellent updates”
About iSailGPS : NOAA USA RNC Charts
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: [email protected]
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 locati
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: [email protected]
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 locati
Latest updates
9.6.9
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.
