There are a host of apps out there, here are just a few which we rate as rather useful... So, in no particular order:
World Cruising Calendar
This is a long-term cruise planning aid, with a global chart for each month that shows at a glance the areas of the world with good sailing conditions for the latitude (shaded blue), tropical cyclones (shaded orange and red), plus both the main and secondary routes taken by yachts around the world during that month. Ice limits and isolines showing the percentage incidence of winds over Force 8 are also indicated, as are prevailing winds and currents.
Clicking on the chart brings up short captions that give a little additional explanation and detail. There's also a table that shows the areas of the world that are viable for navigation, areas that cruising yachts will want to avoid, plus those in which caution must be applied. Clicking on any of the entries will bring up a short text box with more detail.
The app does a good job as a quick and easy visual guide to the world's sailing routes across the different seasons. A neat touch that should help yachts heading in similar directions to stay in touch is a facility to share your position via a social networking style interface.
On the downside, this app doesn't offer the detail of either pilot charts or comprehensive guide books such as Jimmy Cornell's World Cruising Routes, which you will still need if sailing considerable distances, especially off the beaten track. A helpful addition would be a distance calculator between world ports along the typical tracks taken by sailboats – without this it's difficult to estimate how long a proposed passage may take.
As it’s a relatively expensive app this will doubtless put off some potential buyers. However, this doesn't detract from it being a useful presentation of the most salient information to consider at the early stages of planning ocean passages and even at full price it's cheaper than a couple of pints of beer.
Boat Beacon – AIS Marine Navigation
This is the Rolls Royce of the many AIS apps that show the position, speed and course of shipping. While there are plenty of free apps – and websites – that will display this information, Boat Beacon goes a stage further in calculating the calculating closest point of approach of your boat to other vessels. This is based on your GPS speed and direction and the other boat’s transmitted AIS data. In doing so it can help to identify potential collision situations at an early stage.
The app can also act as a tracker, transmitting your position and speed via a web interface. This means that family members, for instance, can check your progress, but unlike an AIS B transmitter, it’s important to recognise that other shipping will not be able to see you on their systems.
The app needs a mobile data connection to operate – and although many coastal waters have coverage, there are notable gaps in this. This may not matter unduly for those on board – after all you’ll only be the position you were in without this £6.99 app – but family following your progress on shore may find it disconcerting if your vessel appears to vanish.
Boat Beacon can’t really be considered a replacement for a proper AIS receiver and display that doesn’t depend on a cell phone signal, but for the price of a couple of beers it’s certainly a useful addition to your electronic aids.
This app helps to avoid those sleepless nights during which you wonder whether or not the anchor is dragging as the wind starts to build. It will trigger an alert if the phone’s GPS position moves out of a pre-defined area, set as a radius around your anchor, varying from 15ft to 75m. You can move the centre of the circle after anchoring, to position it exactly over where you think the hook is.
Alerts include an alarm or flashing message. The app can even call another phone, which would be especially useful if you’re onshore, whether provisioning, at a restaurant, or exploring the local area.
There’s also an off-course alarm that can be useful when anchored stern to a quay, as is common practice in many parts of the Mediterranean. It will alert you should the boat swing away from perpendicular to the dock. Maps are also available as in-app purchases, but these aren’t essential to the basic anchor watch function.
Marine Tides Planner
This provides all the tide time and height info you need in one place for instant access, wherever in the world you sail. Data is provided for more than 5,000 locations and, once downloaded, no internet connection is needed as the database is stored on the device.
The free version gives access to data 24-hours ahead, while in-app purchases can extend this, with the cost varying according to different countries’ approach to making data available.
A neat feature, as the Cowes and San Francisco screen shots show, is the display of the tidal curve, which shows accurately the height of tide at any given time as you mouse your finger over the graph and eliminates any errors when reading the graph.
All the knots you need clearly explained in this app, with step-by-step photography and usage notes. The 35 most useful sailing knots are in a separate category, for easy reference. Similarly there’s a category with 21 fishing knots.
You can also impress your friends with a wide variety of decorative knots, plus other bends and hitches. It also covers eye splices and back splices in three-strand rope, but not splicing braided rope. Similarly there are two whippings – a sailor’s and West Country – but not the (stitched) sailmaker’s whipping that lasts indefinitely.
Nonetheless, there’s a lot of useful info in the app and it’s an ideal reference for new and enthusiastic crew who want to learn to become more useful on board.