iNavx App on the ipad as GPS

[Dunham]

Hi everyone,
I just wanted to let everyone know that the inavx app used on an ipad is what we use as our GPS out on the waters. Believe it or not, it works like a charm and the beauty of it is you don't need network (3G) for the app to work assuming you have the ipad with 3G. Basically, the GPS chip is built in into the ipad - which most people don't know. We sailed to Youngstown NY from Toronto with it. If you need to invest in a new GPS and own a ipad 3G version, we recommend you look into it.

 

[anchorclanker]

I would want to know exactly how it is receiving positioning data. My Palm has a Google Earth GPS app, but it is not using satellites, it uses cell towers. I dont believe any smart phones operate any other way than off cell towers. Once you lose cell coverage you lose the gps.

 

[Dunham]

If you have an Ipad with 3G the GPS chip is built inot the Ipad. no need for cell towers. We were in the middle of Lake Ontario - with no coverage and our GPS still worked. It's a misconception that it won't work. We showed a bunch of people at our marina and they were impressed.

 

[Forrest15112]

Can't speak for specific apps that I'm not familiar with, but all smartphones (3g &4g devices included) have gps receivers built in. The FCC requires all mobile phone companies to deliver accurate location data of users during 911 emergency calls. 3g and 4g networks are not conducive to using triangulation to locate the user. Triangulation is used on non cdma networks such as GSM networks where the mobile device is on a unique frequency. Actually, the cell towers use a method to measure the time it takes packets of data to reach surrounding sites. What makes this fascinating ( to me at least -geek) is that those data packets travel at the speed of light and being able to measure the difference in time it takes specific signals to reach several different nearby cell towers is amazing. It requires extremely accurate clocks at each cell tower that are synchronized with each other. The cell towers each have gps receivers that care nothing about location, but more about the highly accurate clock pulses that allow the necessary synchronization. The time difference of arrival is used to calculate location with very good accuracy.
Long story short, 3g & 4g cdma isn't utilized by cell towers for any type of triangulation. What typically happens is the map data is not stored on the smartphone or tablet and is streaming via the 3g or 4g signal. I have an app on my iphone that allows you to download map data for specific regions of the US which eliminates the need for the data connection. Before I downloaded that data, my navigation app would stop working.

 

[Serena1]

I think there is bit of confusion. Dunham is not using a smart phone. They are using an IPad (not iphone). The standard IPad does not have 3G or gps connection. The standard IPad works off a wifi connection only.

Dunham has an IPad with 3G capabilities. This devise also includes a GPS chip. What they are able to do, is deactivate the 3g connection and only use the GPS capabilities.

 

[Dunham]

That's exactly it. Thanks Serena1

 

[gr8_2_av8]

I have an IPad 3 without a data connection. I am considering purchasing an XGPS150. Anyone have any input regarding this Bluetooth receiver, and how well it works in the mentioned app.

 

[Distance]

I've been using iNavX and it is a great app. However I use it with my DMK box along with a Standard Horizon Matrix AIS to put AIS data on the iPad. It works well with iNavX as well as iRegatta which I use when I'm racing.

www.dmkyacht.com/inavx

 

[JohanB]

I also use my iPhone to navigate with the Navionics app and it works great on my 3G phone. Since I sail the Chesapeake I have not paid close attention to whether or not it works without a cell signal. AT&T is a GSM network I believe so my question to Forrest15112 is whether the GPS in the phone is the location finder or is it the radio tower triangulation?

 

[vtsailguy]

I picked up this trick from the Apple forum.

You can buy a iPad that has wifi and 3G. You need the 3G version to get the gps chips the wifi only does not have one.

Then the sneaky part is that you never activate the phone or data plan.

As long as you are using an app that can preload the maps, you now have gps.

(this won't work with google maps as it uses an Internet connection - aka 3G) to download the maps.