SailTimer app

How to Use
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Frequently Asked Questions

Displaying marine charts.
Please go to this page for the FAQs on how to use marine charts in the app.
What is the difference between the SailTimer app and the Charts Edition?

The SailTimer app is available worldwide, and came out shortly after the iPhone and App Store. The Charts Edition is newer, and is a free version that was initially only available in iTunes in countries where we have hydrographic charts available. It has a lower price to offset the cost of the charts.  Now, both versions of the app are available worldwide in iTunes.  The exact same features are available in both. However, there are a couple features included in the SailTimer app (all-inclusive) that are in-app purchases in the Charts Edition (a-la-carte).

Can I turn on Location Services (the GPS in the iPhone/iPad) after starting the app? You can open the app without using Location Services.  But if you want to use your GPS location, it is best to go into Settings on the iPad/iPhone and turn on the GPS (which Apple calls Location Services) before you open the SailTimer app (or Charts Edition).  If you forget, it is best to hard-quit the app to remove it from memory, then turn on Location Services, then restart the app. (To hard-quit an app, double-click the round Home button then swipe upwards on the app.)
Which iPhone/iPad/iPod has a real GPS receiver? iPhones and the 3G/LTE iPads all have actual GPS receivers in them (not just cell-tower triangulation).  The iPod does not have a GPS antenna, and the wifi iPad (i.e., without cellular data capabilities) does not.  But for those, it may be possible to add a GPS accessory (either plug-in or Bluetooth) from companies such as Bad Elf, Dual and GNS.  (However, in April 2015 several companies noted that iOS updates to 8.3 and 8.4 may disable GPS accessories:  see explanations from Bad Elf and the FAQ on this page from Dual.)  Other customers have also reported success using the Garmin 72 handheld GPS connected to a wifi iPad via a serial cable, serial to USB cable, then USB to Lightning cable. The GPS data must be brought in for Location Services on the iOS device (in Settings), not as NMEA data.
How good is the GPS receiver in an iPad/iPhone? The GPS accuracy on an iOS device is very good, and will rival anything you can get on a dedicated GPS unit.  Apple uses some clever algorithms for interpolating, smoothing and augmenting the GPS location with any other data available, which may include cell tower triangulation, IP addresses and previous speed and direction. However, older iOS devices lacked one important feature that improved GPS accuracy:  they did not support WAAS (perhaps because it is only available in the USA and sourthern Canada).  WAAS uses additional ground stations and satellites that remain in the same place above North America to improve accuracy.  This seems to be why the GPS speed may occasionally blank out on an older iPad/iPhone if you are ghosting along at only 1 or 2 knots.  If you have an older iOS device and wish to improve GPS precision for North America, it is possible to add a GPS accessory such as the ones from Bad Elf, Dual or GNS, which allow WAAS to be used on older iPads, iPhones and iPods. However, newer iOS devices also now add support for the GLONASS satellite system, which gives them near-WAAS accuracy worldwide.
When should I save my GPS track? Although your GPS track can be displayed, if you email it or shut it off, only what has been saved will be used. Make sure to save the track if you want to keep it or email it.  *Note also that displaying a current or previous GPS track could slow down your screen panning (especially on older devices with less ram).  Unselect it if you are not using it, by turning the tracking on/off.
Is there a version for Android? Yes, we have a wind gauge app for Android.  We haven't added charts to that version yet though, while evaluating some security issues since Android apps and content like charts in them can be shared online.  We would not be able to license government chart data if the charts were being distributed freely online. That is protected in the iTunes app, but we are working on security approaches for the Android app before adding charts to it.  So for now, the Android version is a standard display of wind speed and direction for the SailTimer Wind Vane.
Can I get the app in iTunes on my computer with one Apple ID, and then do in-app purchases on my device with a different account? No, Apple prevents this.  You must do the in-app purchases with the same account you used to get the app.
How do I use my existing ActiveCaptain account in the SailTimer app? You do not need to register a new ActiveCaptain account.  Just do the in-app purchase.  Then the Log-In button will turn blue, to indicate that you can now log-in using your existing ActiveCaptain userid and password.
Can I save, rename and delete waypoints?

Yes, use the Tacking Routes button (upper left corner of screen) to make waypoints -- either a single waypoint, or a route with multiple waypoints.  This is the method in v. 5.6.1 and newer.  Earlier versions used a button  labelled Drop Pin (upper right) to save a waypoint.  After placing a pin, a new button appeared on the top bar appear called Set Waypoint, to save it.  Waypoints could be named with the Waypoints button (top left).  But since March 2015, rather than just specifying a single waypoint, you can set a Tacking Route and see your optimal tacks as you move through a series waypoints, as in this screenshot.  You can also paste in a list of lat/long coordinates to create a Tacking Route.

Will the app work on a device without GPS? Yes.  If you are using an iPad with no GPS or an iPod Touch, you can still do all of this.  Drop a pin on your location, and you'll see a button show up at the top of the page called Set Current Position.  Click that, then you can proceed to see your optimal tacks from there.  (*New buyers:  you can buy the version of the iPad with the GPS in it, and never use the cell data connection. You don't need a sim card.  All GPS functions will work fine.)
What other products use the patented SailTimer technology? If you want a more durable handheld that is viewable in direct sunlight, we also manufacture The Sailing GPS. Also, since 2006 we have licensed the SailTimer methods to full-featured computer chartplotter programs from MacENC (also sold by Fugawi) and NavSim.
Can I switch tacks to go around an obstruction? Yes, you can switch to the other tack using the "< >" button in the bottom-left of the screen when optimal tacks are displayed.  The results are the same whether you do the port or starboard tack first (or whether you do 10 small tacks on those headings or two large ones).  As you will see, this button lets you display the port or starboard tack first.  It also has an automatic mode, where if both tacks are the same length, it displays the tack first that is closest to your current heading.  Setting a closer waypoint will also let you control your course to go around obstructions. 
Why doesn't the app show the other tack sometimes, when I press the <> switch tacks button? If you try to switch tacks and the green lines do not move to the other side, it means that with the given wind andbearing to the waypoint, the other tack will not get you there as quickly.  The tack switches from one side to the other when either side is equally good.
Can I check the tacking results to different possible destinations before leaving?

Yes. The most useful thing with all of the different platforms that SailTimer has run on has always been planning out the tacking route before you cast off. You have to be moving to use VMG (Velocity Made Good) or telltales on your sails. But with the SailTimer app, just enter the wind direction, wind speed and a waypoint, to see how long it would take to sail to different possible destinations, and the optimal tacks to get there.

How can I save my battery power? If you want to continue to update your optimal tacks and perhaps document your GPS track, you can shut the iOS device off.  That will save power from not lighting the screen.  If you are marking a GPS track, it will continue when you shut off the device, or when you exit the app. Unselect it in the Options if you want to stop it.  *For the best overall power savings on your device, shut off Location Services (the GPS) when using the app for other purposes. 
Can I send wind data from my old wired anemometer to the app?

Yes, this may be an inexpensive way to get wind data into the app to calculate tacking results, if you already have a legacy anemometer in an onboard network.  (Although the wireless SailTimer Wind Instrument may be more cost-effective if you still need to buy a multiplexer.)  There is an in-app purchase in Input\Setup\Onboard Network that allows you to receive wind data using wifi (UDP) with the MWV sentence in NMEA 0183 format.  You may be able to transmit this from a GPS chartplotter with wifi, a computer running a chartplotter program, or the NMEA multiplexer from Digital Yacht. The SailTimer app (and CE) can also now receive wind data in UDP wifi transmissions from the iKommunicate device, which can receive and convert between NMEA 2000, 0183 and Signal K formats. 

The app is currently not compatable with multiplexers from DMK, Shipmodul or Brookhouse.  With the DMK Box, the reason appears to be that with our wireless anemometers, the app is the server and the wireless sensor is the client, but that the DMK Box may also be set up as the server.  With Shipmodul, the Miniplex uses an IP address that is different than the one expected by the SailTimer app (or Charts Edition).  But there may be a workaround... If you are having trouble connecting through a wifi multiplexer and have a wifi router on board, you may be able to send wind data to the app through the router instead. 

What about lifts and headers, for racers? In his 1948 book Yacht Racing and the Aerodynamics of Sails and Racing Tactics (originally published in 1928), Dr. Manfred Curry describes the strategy to "tack in a header" when racing to an upwind mark.  In a header, the wind shifts, causing your heading to move away from the destination.  If you tack then, you can take advantage of a more direct line to your destination on the other tack.  Although he documented that racing tactic in the previous century, with GPS and digital calculations SailTimer continuously evaluates and displays your optimal tacks (especially if you have real-time wind data coming in from the wireless SailTimer Wind Instrument).  You can toggle the port and starboard tacks in the SailTimer app to see how the other tack looks.  You can also stay on those headings in lots of small tacks close to the rhumb line. The SailTimer app doesn't assume that there was an average wind direction over some previous period, and then try to warn you about a header;  it just continuously updates the display of your optimal tacks.  This is clear and effective, and you can still use his original strategy to go onto the other tack in a header if you see the green tacking lines move in a header. 
Can you toggle between True and Apparent wind if you use the SailTimer Wind Vane with the app? Yes.  Click on our unique wind speedometer to make it larger, and you'll see a button in the top right to switch the wind speed and directin between True and Apparent. Whichever one you leave on the big wind speedometer is what is also displayed on the chart, for the wind speed and the grey wind arrow for wind direction around the yellow boat icon.
I know my boat's polars -- how can I edit them in the app? To edit a polar, email it out of the app to yourself. Then edit it in a text editor, to add values for your boat for the wind angles and speeds in the table. The software will look after the in-between values automatically. Then email it back to yourself, to receive on your iPad/iPhone.  Click and hold on the email attachment and it will say "Open in SailTimer". Then you'll have your own polars in the app.
The table for polar learning only shows certain categories for the wind angle and speed.  Are in-between values accounted for? Yes - the table can't show every value, but the software does use in-between values, the same as they are shown on a polar graph or plot.  The table such as in this screenshot is used for simplicity and for exporting.  But the software actually uses a continuous function. You can actually see this yourself during polar learning.  If the wind angle is at e.g. 40 degrees, in-between the 22.5 and 45 degree wind angles, you may see the polar learning influence the boat speeds on either side.
When the API for the wireless SailTimer Wind Instrument was upgraded to v. 1.2.4, why couldn't my SailTimer app or Charts Edition receive the wireless data anymore? A proprietary data sentence was added in the API for Apparent Wind Speed and Apparent Wind Direction, to give them more accuracy when displayed in other apps.  If you use the SailTimer app or SailTimer Charts Edition with this new version 1.2.4 (or above) of the API, you will need to update the SailTimer app or Charts Edition to 5.7.3 or newer in order to receive data from this new version of the API.

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