It’s been a couple of weeks since my last post and after traveling for a while I have returned home and it’s long overdue to write some blog posts again. The first topic that comes to mind is iPad navigation. During the Atlantic crossing but also other professional deliveries I had multiple captains use iPads for their primary means of navigation. Even though the yachts were outfitted with GPS plotters and sometimes the latest and greatest of stuff the manufacturers had to offer (like the B&G setup on Dancing Queen) all captains I’ve sailed with used an iPad for navigation.

So here’s my take on the matter, use my opinion as you see fit. But remember it’s my opinion based on my experiences and yours could be different and that’s totally fine.

Paper charts

Stuart, Yvan and myself working on plotting our trip on paper charts (February 2023)

So back to where it started: Paper charts! During my RYA YachtMaster training it was the primary form of navigation. Yes you were allowed to use a GPS to plot your location, but you still needed to do it all on a paper chart. From dead reckoning, estimated position, fix, bearings, course to steer, blind navigation. It’s all done on paper charts and the skills are invaluable if your electronic devices fail. But it’s 2024 and back in 2022 UK Hydrographic Office (UKHO) has announced that it will be phasing out the manufacturing of paper charts with the aim to completely end production by late 2026.  So with charts ceasing to exist in the next years many sailors turn to electronic devices like the iPad. This has lead to the rise in navigation apps like “Navionics” and many others.

Obviously for years some sailors have been running other navigation software like “OpenCPN” and others on their Asus EE-pc in the day. I’ve done so myself on my previous boat too. But with the introduction of apps anyone without tech skills can download any navigation app and start using it.

The tablet as a plotter

Just a step away from the iPad as a branded product and almost being synonymous to the term tablet. There are many manufacturers out there with a touchscreen enabled handheld device. I think its important to note a couple of differences between a tablet and a “real” plotter from companies like Raymarine, B&G, Garmin etc.

First one is the build quality: A tablet is not specifically made for rough salty environments, some versions of rugged devices exist. But in general they don’t like seawater sprayed all over them. Most “real” plotters have no issues with that.

Secondly a tablet is a removable device. There are holders and charging cables available, but if you have a rough storm and you like to have the tablet outside it could get damaged or lost if you get in rough weather. Also the power connector usually does not like salty air/water/spray and will suffer from corrosion. So most captains I’ve seen only used the tablet (iPad) inside on the nav table.

Thirdly the accuracy of the internal GPS sensor. Most tablet GPS sensors or apps don’t show the Horizontal dilution of precision (HDOP) value. Which means that the tablets position could be off a couple of meters or by a mile. And that could be dangerous when relying on the tablet for navigation dangerous areas. Any sailor using a tablet for navigation purposes should be aware of this matter. Some apps show the accuracy of the GPS in one way or the other. But be aware that it’s not a constant factor. All “real” plotters I’ve used over the years show the HDOP value somewhere in the software, usually on the satellite details page.

With these three important comments in mind, let’s continue to use our tablet for navigation as it’s handy and efficient.

My experience

Ever since I’ve owned an iPad I’ve been using Navionics, like everyone else that uses an iPad for navigation. On all my sailing I use it to plot a route from the comfort of my home or salon aboard, and then later transfer the route data to the ships onboard plotter (Or delegate the data entry haha, see photo below).

So I primarily rely on the ships GPS sensor and navigation devices. I usually leave the iPad running to track my trip or turn it off completely. This works fine for me, and I don’t worry that my tablet get thrown around in bad weather.

Stuart entering our paper chart planned route in the Raymarine Axiom plotter.

On my Cruising Instructor training one of the guys there told me about an app called iSailor and he told me it was much more advanced and professionally maintained than Navionics. So I downloaded the app and tried it out. I found it had some benefits but also drawbacks versus Navionics. The biggest benefits were Night mode, and the overal look and feel and features of iSailor appealed to me.

When I was sailing as a charter captain in Greece the whole team used Navionics to plan, share and discuss the routes for that week. Like a good captain I transferred the routes into the onboard plotter and sometimes I exported the routes and imported them in iSailor. But I found that after a while I didn’t even bother to plan the route in the onboard plotter anymore. I had other things to do like getting the vessel ready to receive guests and depart. And after a couple of weeks you know the area by memory so you don’t really need a chart anyways.

When I had some time off in the weekends I’d think about navigating this way and It’s all fine and dandy when the weather is nice. One time we had to depart just before a storm would hit and I found myself in a hurry to plot that week’s trip in the onboard plotter anyways. And when the storm has passed I was back to business. And I used Navionics and iSailor side by side to get a good feel for both apps in their most recent versions.

I found that Navionics was very slow to start and heavily consuming power while running. iSailor was more forgiving on the power consumption but crashed sometimes for no apparent reason. From a navigation experience and the ability to run the app in dark/night mode I grew a preference for iSailor over Navionics.

When I was part of another delivery: The ships multi inverter short circuited rendering all electronics (230v, 24v, 12v) aboard useless as the boat went completely dark. No GPS, No plotter, No VHF, no Navigation lights, nothing! In the middle of the night in a busy shipping area. We were happy that we still had the Captain’s tablet with Navionics and I had my iPhone with both Navionics and iSailor. So when daylight was back again we could safely head to port. Which shows the iPad (or tablet, phone) is a perfectly valid back-up device.

The captain on the Atlantic crossing had planned the whole voyage on his iPad and I was pleased to see that he had done it in iSailor, so it was easily imported into my iPad. But he also had the same route on Navionics as a ‘backup’. Which was funny because it’s still in the same physical device so what are you protecting against? Software corruption is the only thing I can think of.

I used iSailor for the entire crossing to track my location (apart from the iridium tracking) and we used the captains iPad running iSailor for the navigation and route calculation. But as the boat’s log didn’t work we had to open Navionics and place markers every watch change so we had a digital log of where we were. (Obviously we kept a paper logbook too)

So it was quite annoying working with all these apps, while the boat had a perfectly fine working Raymarine Axiom plotter. And I’m still amazed that no effort was made to transfer our route into the plotter. It was basically one line between two waypoints so how much effort is that? On the other side: What’s the actual benefit on a leg that long?

I found iSailor frequently having issues on both tablets. The captain’s frequently froze or had no GPS location and the app on mine just crashed and therefore didn’t log any tracking information anymore. These issues don’t really matter on the ocean as long as you know where you are and which course you need to go. But it got a bit annoying.

iSailor losing track because of the app frequently crashing

Now that I’m back home and thinking about my upcoming sailing season with BAIA I’m also thinking about what to do with iPad navigation software. One of the main annoyances for me is that I need another app for weather information (like PredictWind or Windy) and that it doesn’t overlay in the navigation software. Navionics has some options to do that, but its not great in my experience.

So I set out to find another solution that combines the best things I like in Navionics and iSailor. And then I found iBoat from TimeZero. This blog post is not an advertisement and I’m not being paid to write or test this. But on first glance this app looks promising.

TimeZero iBoat Raster v.s. Vector chart modes.

So I’ve downloaded it, subscribed to some charts and I will see if it does what it says on the box. Upon playing for the first hour with the app in the comfort of my home the interface seems intuitive and stable. So first impression is good, but so was mine with Navionics and iSailor…

BAIA has two Raymarine Axiom plotters which I will remain to use as my primary navigation device. So I’ll need to update the charts for this season, and I’ll run iBoat in parallel to experience. To connect the iPad to the boats NMEA2000 network I’ve ordered an Actisense W2K-1 gateway which will replace my Actisense NGT-1-USB which I don’t use. And I’ll post about my experience with that device somewhere in the future.

If I’m doing a delivery or charter work I’ll primarily use iBoat as my own navigation device. But obviously I’ll keep transferring the route information into the onboard plotter (if available).

Rounding up

So I guess you are thinking: “Cool story bro! Now what should I do?” And I think every situation is different but in general: If you don’t have a “real” plotter aboard its perfectly fine to try out a tablet and any of the apps like Navionics, iSailor or iBoat. As long as you keep the tablet safe and secure and keep note of the (in)accuracy of the GPS sensor.

If you still need to buy a tablet: Don’t ask me anything about the Android ones, I’m using Apple products for a long time and my experience with the iPad has been great. I don’t think iSailor and iBoat even run on Android. But if you need to buy an iPad: Make sure you get the “cellular” enabled version.1 Otherwise no GPS sensor.

Navionics does not show any information on GPS accuracy. iSailor has a “Primary GPS Low Accuracy” Alarm which you can enable in Settings > Alarms. iBoat only as a “GPS Location Lost” alarm so that doesn’t help for the Accuracy. As I’ll be connecting iBoat to my onboard GPS that accuracy issue becomes less of an issue.

If you have a plotter onboard, maybe use both side by side. Even if it’s an older model that still works fine. You only need to pay twice for your charts but I think the safety is worth it. And you could basically keep the paper charts down in the nav table.

Personally I would not mount my iPad outside so I can view or use it like a “real” plotter while at the helm position. If you decide to do: mount it properly and keep it away (and clean) from salt.

I’ve read online that Wärtsilä (who own iSailor now) doesn’t actively develop on the iSailor app. They just sell the chart subscriptions and hardly make any updates or fixes to the app itself. I’ve also had one issue with restoring purchased charts and sent them a support e-mail which they never replied to.

Garmin owns Navionics so that app will be properly supported. I only feel that it’s currently very slow to start the app (everyone complains about this so its not my device) and its heavy in power consumption.

So I’d take that into account when deciding which app to download.

In a couple of months time when I have some experiences with TimeZero iBoat to share I’ll write another blog post with my findings.

  1. Newer models could have GPS without the need of the Cellular modem. Please do your own research before buying an iPad. ↩︎