GPSmap 172c --- GPS Replacement Options

[Ted Pounds]

Currently cruising the Rideau Canal and associated lakes on a houseboat. The navigation system is an iPad with no cell service and internal GPS. It uses Navionics chart app. It is left plugged in continuously to a USB charge port at the helm station.  It also has a waterproof case.  It is an outstanding navigation aid. Better than what I use flying the B-787. I can't imagine a better system at any price. 

[KWKloeber]

use an iPad as a chart plotter.

Just an FYI.  You have to be careful about iPads and GPS.  (Unless Apple has changed its ways) only the cell-enabled iPads have an internal GPS chip.  The WiFi (only) iPads don't -- they use wifi networks and cell towers (even w/o an active cell contract) to determine the "gps" location, so it can at times be very approximate.  Even the iPads w/ gps chips initially use WiFi and cell to get the first (approximate) location (recall that your gps takes a while to lock onto enough satellites to start displaying a good location. So when first turned on, an iPad couldn't possibly lock onto GPS as quickly as it appears to find the location -- it's fooling us.)

[Stu Jackson]

There have been, and will continue to be, detailed discussions about this topic.  Kinda like asking your mom what girl to marry before you've had a first date, or "What boat should I buy?" 

Here's another good recent one:

http://www.cruisersforum.com/forums/f13/new-iphones-and-the-imminent-death-of-the-mfd-223683.html

[Noah]

Ken— that is why I mentioned using a GPs plugin/dongle device for iPad such as a Garmin or Bad Elf add-on.

[mark_53]

use an iPad as a chart plotter.

Just an FYI.  You have to be careful about iPads and GPS.  (Unless Apple has changed its ways) only the cell-enabled iPads have an internal GPS chip.  The WiFi (only) iPads don't -- they use wifi networks and cell towers (even w/o an active cell contract) to determine the "gps" location, so it can at times be very approximate.  Even the iPads w/ gps chips initially use WiFi and cell to get the first (approximate) location (recall that your gps takes a while to lock onto enough satellites to start displaying a good location. So when first turned on, an iPad couldn't possibly lock onto GPS as quickly as it appears to find the location -- it's fooling us.)

The iPad Air uses (both wireless and cellular) GLONASS for out of coverage location data.  Here's the specs from Apple...


Wi-Fi + Cellular models

    Assisted GPS, GLONASS, Galileo, and QZSS
    Cellular

[DaveBMusik]

I use a Garmin 4210 at the helm. I purchased a year old Chart SD card for about $99 (Garmin will update it to the newest version one time). I installed a Vesper 8000 AIS which includes a WiFi signal. I use Aqua Map on my iPad which is one of the few programs that will accept the Vespers GPS location (no cellular version needed although mine is). Aqua Map also updates all the Active Captain info. I also have the Garmin 78 handheld as a third backup (which I have only used in the dinghy to get back to the boat in the fog :) ).
So, I have one year old charts on my 4210 at the helm with it's GPS Antenna reading AIS info from the Vesper, I have my iPad available using AquaMap and Navionics for problem areas (where updated info is crucial) as well as for AIS and Active Captain using the Vesper's GPS Antenna, the iPad's own cellular GPS antenna if the ship's electronics go out, my rarely used 78 and then (gasp) paper charts.

[KWKloeber]

Ken— that is why I mentioned using a GPs plugin/dongle device for iPad such as a Garmin or Bad Elf add-on.

[something else that I didn't realize - When you use an iPhone or iPad to geotag a photo, the accuracy is about 100 feet (about 30 meters), because Apple only stores GPS data down to the nearest second in latitude and longitude - geospatialexperts.com/ipad-gps/]

AhhhSo -- I didn't take it that you were referring to the WiFi (only) pads.  Just wanted to peeps who might be considering a WiFi only, realize that after all that, they'd need tpo plunk down another bill after the fact to get gps.

The last time I looked into this, I recall there were issues with the iPad (or maybe it was specific apps) being able to use or accept any old tethered external gps - hopefully, that is much better now.

-k

[DaveBMusik]

use an iPad as a chart plotter.

Just an FYI.  You have to be careful about iPads and GPS.  (Unless Apple has changed its ways) only the cell-enabled iPads have an internal GPS chip.  The WiFi (only) iPads don't -- they use wifi networks and cell towers (even w/o an active cell contract) to determine the "gps" location, so it can at times be very approximate.  Even the iPads w/ gps chips initially use WiFi and cell to get the first (approximate) location (recall that your gps takes a while to lock onto enough satellites to start displaying a good location. So when first turned on, an iPad couldn't possibly lock onto GPS as quickly as it appears to find the location -- it's fooling us.)

The iPad Air uses (both wireless and cellular) GLONASS for out of coverage location data.  Here's the specs from Apple...


Wi-Fi + Cellular models

    Assisted GPS, GLONASS, Galileo, and QZSS
    Cellular

From Apple:

Location
Wi-Fi
Digital compass
Wi‑Fi
iBeacon microlocation

Wi‑Fi + Cellular
Digital compass
Wi‑Fi
Assisted GPS and GLONASS
Cellular
iBeacon microlocation

I take this to be as it always has been, you need to have the cellular version on order to have wifi OR external dongle OR wireless signal from an external GPS such as the Vesper 8000 AIS