SeaNav – Portuguese charts

SeaNav now has vector charts available for Portugal, The Azores and the Madeira islands based on the latest official Hydrographic Office data. These work seamlessly together with the existing charts for Spain and France. The charts include the full range of scales down to harbour approaches.

You can download the new Portuguese charts now by going to Settings in SeaNav and selecting SeaNav Chart Store/Portuguese Charts.

Lisbon Harbour entrance

SeaNav – Export and import routes via email

The simplest way to share a route with one of your other devices is to export a route via email to an email address you can read on the other device. The other way is to use Dropbox if you have a Dropbox account. Dropbox is bit more “automatic” once you have logged in and lets you browse your saved routes.

This article explains how to do it via email.

Tap the “zigzag” routes icon on the bottom toolbar and select Manage routes. Select the route you want to export by tapping the i button on its right. Then tap the share icon on the left toolbar ( square with arrow pointing out of it). Select Email as kmz and then fill out the email address to send to.

Open the email on your other device. When you open the email there will be a kmz file attached at the bottom of the email. Tap the kmz file image to download it

and then tap the share button bottom left to open it (2) .

Choose what you want to open the download with – scroll along or tap more if you can’t see SeaNav in the initial list of icons – choose SeaNav and it will import it and open SeaNav on the new route.

SeaNav and an autonomous boat

We have downsized the Pocket Mariner test boat from a catamaran cruiser to a catamaran dinghy (Dart 18) and are doing our bit for Net Zero and our ears with an electric outboard.

We chose the Torqeedo 1103C which has slightly more power than an e-Propulsion and also had the benefit of being available rather than on a 6 month back order. It is a revolution compared to a petrol outboard. Totally silent apart from the sound of water flowing past the hull, instant start, no oil or smelly petrol and fumes. A real joy, here is it in action on the river Wye:-

As well as using the test boat for testing our marine navigation apps we got inspired to take the boat to the next level and see if we could automate it and ultimately use SeaNav to control it to follow a SeaNav route.

Two steps:-

  1. A bluetooth LE enabled autohelm attachment to control the outboard direction
  2. Add the bluetooth driver capability to SeaNav and get it to maintain course and change course at Waypoints.

A possible 3rd step is to add a remote throttle control too so we can go fully autonomous!

This article covers step 1.

Step 1. Bluetooth iOS remote for Navico TP5000

Autohelm units are very expensive ( over £400) and none offer remote bluetooth control. We couldn’t find one that supported remote NMEA0183 control either. So we bought a second hand Navico TP5000 unit off eBay and adapted it to support Bluetooth using an Arduino BLE nano33 board and 3 relays attached inside the housing to the switches. The project design, instructions and code is here This could also be adapted to control a Raymarine Autohelm unit.

Here is the Navico TP5000 in manual mode attached to the boat and Torqeedo outboard:-

and here is the TP50000 controlled with our iPhone autopilot app:-

Next is to test this on the water and then move on to Step 2…..

Please contact if you have any questions or suggestions.

Setting up club race courses with SeaNav

You can use SeaNav to enter and edit race courses, share these with others and navigate the course. Typically a club will have several race marker buoys and on any particular day set up a course using a subset of them plus possibly other fixed buoys in a particular order to best suit the conditions. This article shows you how easy and useful it is to do this using SeaNav in three easy steps:-

  • Ready. Enter all the race markers as POIs ( and use the SeaNav yellow flag race marker style). Typically you only need to do this once a year or less.
  • Set. Create a route from the ones you want to use as the course.
  • Go. Start racing the course.

First step – Ready. Set up all the club’s race markers as POIs in SeaNav. For this example we will have 5 race marker buoys labelled A through E. Create each one by long pressing on the chart and tapping “Add POI here”

You can enter the buoy name in the edit screen that pops up and also choose the marker type (icon on left above the name field) e.g a yellow flag for a race marker). You can edit the Position Lat/Long if you want to make it more precise/accurate. You can also import the markers from kmz files.

After adding all the race markers, which you typically only need to do once a season, the next step is to set up the course for the day.

Second Step – Set: Enter the course as a New Route.

Tap the route/poi symbol on the bottom toolbar and then tap “New route”

Enter a race start Waypoint or tap the POI race marker you want to be the start of the race and select “Add Waypoint for POI”. “A” in this example. Cycle through the rest of the markers in the order you want them adding them as waypoints . Here we are adding C and D and then ending back up at A.

You can end back at the start or at a different marker. You can set a race start/end line using a start and end waypoint markers. Enter a name for the course/route now or later in Manage Routes. Tap Done when you have finished. You can now share the route with others via email or dropbox and also send it to your own email as a back up. In Route details you can see the overall route length and distances between waypoints.

Final Step – Go: To start sailing the course just tap the Sailboat icon bottom left. It will mark the first course mark of the race with a star and show you the distance, bearing and ETA to it. When you reach it, SeaNav will automatically set the next race waypoint for you. You can manually choose the next waypoint in the route using the forward and back tab arrows in the navigation HUD at the top of the screen.

Get racing and good luck!

Tidal Streams for SeaNav

You can now view the current and predicted tidal flow rates and directions live on SeaNav’s UK and IE vector charts.

We use the official chart Tidal diamond symbol, rotating it to point in the flow direction. Blue means the rate is decreasing, red and its increasing. The diamonds update in real time on the chart. For planning tap on a tidal diamond to see the rate and direction, tap i for more information and see the rate and direction for the next 3 days on a graph at the bottom of the screen. Slide the time cursor ( or just tap at the time you want ) and all the tidal diamonds in view on the chart update as you adjust it (not just the one you have selected). You can zoom in and out of the graph timeline using pinch gestures. The Tidal Stream information is cached for up to 7 days so will work when you are out. of internet coverage as well.

The new Tidal Stream feature requires SeaNav 5.3 or later and uses official data from the UK Hydrographic Office, updated annually. A current UK & IE chart subscription is required to view the data. We hope to add Tidal Streams for other areas where available if they prove popular ( FR, NL & BE, DE… ). Please email us and let us know.

Entering routes and waypoints with SeaNav on a Mac

Here is how to enter routes and waypoints in SeaNav Mac
Left mouse click on the chart and select “Start new route here”
Screenshot 2019-05-21 at 12.48.31.png
A green pin will be placed on the map and the Navigation panel will display on the left with the first waypoint information.
To add the next waypoint move to another point and left mouse click and select “Add waypoint here”.

A red pin will appear with a blue line (route) from the first pin.
Screenshot 2019-05-21 at 12.48.59.png
You can add as many waypoints as you require and drag and drop the waypoint markers using a long mouse select on them.

Tap the i button on a Waypoint to give it a name ( optional) and view the full lat and long position ( including when you drag and drop it) so you can set its location precisely.

Screenshot 2019-05-21 at 12.53.03.png
Click on Done when finished and you can then sail the route at any time by pressing Sail. You can also select a previously saved route, Sail it , edit it or export it.
You can add a set of existing waypoints from a spreadsheet following this blog article:-
Here’s our guide on iPhone which also has some relevance to Mac. You can also export/import routes between the iOS SeaNav and Mac SeaNav app and also view them in Google Earth.
You can view the routes at any time by tapping the Navigation tab – there is a Demo route in the Solent included with the app that you can use to play with (tap the i button to view the route details and select Edit Route) :-
Screenshot 2019-05-21 at 12.58.45.png

How to import lots of Points of Interest using SeaNav POI csv to kmz converter

SeaNav lets you add individual Point of Interest (POI) at a tap of the screen in the app but what about importing a list of POIs that you already have? We have set up a service to make creating SeaNav Points of Interest from a list of latitudes and longitudes easier and faster. Simply upload a CSV file ( spreadsheet comma separated values) of the POIs using this web link

A SeaNav ready kmz file will be downloaded to your desktop which you can then share and import to SeaNav via email or Dropbox. You can also view the kmz file in Google Earth.
The format for the csv file is very simple and contains one or more lines with:-
name,type (integer 1-6),description,longitude(DD.DDD),latitude (DD.DDD)

e.g. Bass here,3,Good spot,-0.473850,50.291134
The POI types are:

  • 1.  general
  • 2. hazard
  • 3.  fishing spot
  • 4.  diving location
  • 5.  race markers for club racing
  • 6.  favourite harbour or anchorage spot
  • 7.  bridge

These set the POI icon to be used as well.

The description can be html markup including an image link e.g.

“<img src=’’><br>Inlet</br>”

Be sure to wrap html descriptions in quotes as above.

There is more about SeaNav POIs here

SeaNav Favourite Places – Share POIs and Routes

and we have a large database of existing and publicly shared POIs including Marinas and Harbours that you can view and send to SeaNav here :-



How to create and edit a route with SeaNav

Here is a quick guide on how to add a new route in SeaNav

Tap the route button at the bottom of the screen.

Long press on the chart where you want to add a waypoint and tap “Add Waypoint here” on the popup.

Add the next waypoint in the same way

And a third and as may as you want and then tap Done when you have finished. You can move the waypoints you have already added using a long press on one to select it and then dragging it to the desired position. You can also edit the exact position (latitude and longitude) later in the Manage Routes view.

After pressing Done the route will be shown on your chart. You can then start sailing the route or tap the Route icon again to Edit or Manage your routes.

Tap Manage Routes to see all your routes and select a different one of manually edit the current one.

Tap the i button next to a route to see more detail. You can also edit the fields on the detailed view. For instance change the route name from Route2 to Cardiff. Tap the i next to a Waypoint to add names for the waypoints and edit their precise latitude and longitudes. You can enter the latitudes and longitudes in most formats ( e.g. Degrees Minute Seconds, Degrees Minutes and Decimal Degrees (e.g. 52.1345) ) and you do not need to enter the degree, minute or second symbols. Here are some examples:-

DM : 28° 52.634 ́ N can be entered as 28 54.634

DMS :28° 52′ 48″W can be entered as 28 52 48W or   -28 52 48

This view also lets you export the route via email or dropbox to share with others, keep a backup or share with your iPad or Mac (tap the box with an arrow going upwards from it).

If you have any questions please email us at or view the SeaNav User Guide here:-

SeaNav Augmented Reality goes Vertical

Never get stuck under a bridge again! We are pretty excited about the unique Augmented Reality (AR) feature we have just added to our popular SeaNav  iOS marine navigation app. Set a SeaNav POI (Point of interest) marker for a bridge (or cable) on the SeaNav map view, set your boat’s Air Draft in SeaNav’s settings (5.5m for our test boat with its mast down) and see this as you approach the bridge in SeaNav’s AR view on your iPhone or iPad:-

This is one of the 3 low bridges we have to pass under on a tidal river around High Tide (12m at Springs) to get out to sea from our mooring. With the horizon line lined up with the sea level at the bottom of the bridge, the bold red line shows the height of your boat at the bridge. With the latest iOS camera APIs we can get the FoV parameters for any iOS device which allows us to do the relative drawing. The SeaNav POI feature comes included with our free version of the SeaNav App, Air Draught is now included as part of the SeaNav Pro In App Purchase feature ($10) which adds Augmented Reality and live ship AIS positions.