GPS is built in the WIFI only

Lamonster

macrumors regular
Original poster
Dec 4, 2008
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My ipad is at my home in East TN but I've been playing with the one I ordered for my mom here in San Diego. There was a debate as to if the wifi had a gps built in or not. I'm sure you all know this now but it does and I've used it on the maps app and the weather apps. That is a big plus to me. It's working great on Mywi too. This thing is so cool and I'm so glad I got it, I just wish the one I'm playing with was mine.

I am having a little trouble hitting the external buttons when I rest it on a table but other than that this thing rocks.
 

Mark Booth

macrumors 68000
Jan 16, 2008
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Sorry, but the WiFi-only model does NOT have a GPS.

The WiFi-only model CAN locate you via WiFi location services. But if you aren't within range of a known (mapped) WiFi hotspot, the WiFi-only model can't find squat.

You can look at Apple's specs for yourself:

http://www.apple.com/ipad/specs/

Under Location:

• Assisted GPS (Wi-Fi + 3G model)

Mark
 

Stetrain

macrumors 68040
Feb 6, 2009
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I think what you're seeing is the Skyhook WiFi triangulation like the iPod touch has. If you were on a highway no WiFi signals within range you wouldn't be able to locate.
 

Lamonster

macrumors regular
Original poster
Dec 4, 2008
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So my mom has a wifi connection at her house, you're saying that's where it's getting the gps location?

If that's the case then it should work the same if I'm out and about using my iphone with Mywi?
 

Mark Booth

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Jan 16, 2008
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So my mom has a wifi connection at her house, you're saying that's where it's getting the gps location?

If that's the case then it should work the same if I'm out and about using my iphone with Mywi?
As Stetrain mentioned, Apple contracted with Skyhook Wireless for WiFi location services:

http://www.skyhookwireless.com/devices/

Their agreement dates back to the very first iPhone. Skyhook Wireless employees literally mapped the location of WiFi hotspots by driving all around the country in specially equipped vehicles that detect a WiFi hotspot AND map each hotspot's GPS coordinates. That information is fed into a database and the original iPhone used that information to allow location services. HOWEVER, the original iPhone also provided cell tower triangulation. But, more important than that, the original iPhone had an internet connection (via cell towers) when it was near a known WiFi hotspot but didn't have access to USE that WiFi hotspot.

You see, without an internet connection, the data from Skyhook Wireless' database can't be downloaded. So, it's not just enough that the WiFi-only iPad be NEAR a mapped WiFi hotspot, it must have ACCESS to that WiFi hotspot.

So, if you are driving down the road (or walking down the street) with your WiFi-only iPad, it can "see" WiFi hotspots all day long but if it doesn't have any access to the internet, the Skyhook database is worthless to the iPad.

The original iPhone did OK with location services but it was actually pretty slow and inaccurate compared to the iPhone 3GS. The addition of a real GPS made a world of difference in accuracy, particularly when the iPhone was near a WiFi hotspot that wasn't in Skyhook's database (new hotspot or a spot where they have switched out their WiFi base station since Skyhook mapped it).

So, back to the WiFi-only iPad... it is even less effective for location services than the original iPhone. It doesn't have a GPS OR a cellular connection to the internet. The WiFi-only iPad cannot be used to navigate from one location to the next unless there are mapped WiFi hotspots along the entire route AND you have full access to those WiFi hotspots along the route.

Finally, regarding your MyFi.... The iPhone and iPad see the MyFi as simply another WiFi hotspot. It will give you a constant internet connection but the MyFi itself won't give location information because it has not been mapped by Skyhook Wireless. However.. if you have both a MyFi connection to the internet (and Skyhook's database) AND you are constantly near mapped WiFi hotspots, you would be able to navigate. But good luck with finding mapped WiFi hotspots as you drive down the highway or explore less densely populated areas.

Bottom line: If you want to use the iPad for navigation, you have to get the 3G version with GPS.

Mark
 

Stetrain

macrumors 68040
Feb 6, 2009
3,547
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So my mom has a wifi connection at her house, you're saying that's where it's getting the gps location?

If that's the case then it should work the same if I'm out and about using my iphone with Mywi?
It looks up the surrounding WiFi access points in a database that has records for where they are on the map.

It wouldn't work with Mywi because the database doesn't know where your iPhone is if you move it. :)
 

Lamonster

macrumors regular
Original poster
Dec 4, 2008
129
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Thanks for the education, I didn't know how it worked but now I do. I have a real GPS when I need one and my 3Gs works great for what I need it to do gps wise so I'm still good with the wifi only ipad. :cool:
 

Mike Reed

macrumors regular
Apr 3, 2010
166
12
Columbus, OH
I had assumed it used some sort of ip lookup to determine location. I live in a fairly rural area and as far as I've ever noticed I'm the only wifi in the area.
 

Stetrain

macrumors 68040
Feb 6, 2009
3,547
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I am not convinced it does not have gps. It is far too accurate.
Why would it have GPS? Unless you had an always-on internet connection, GPS wouldn't be any more useful than WiFi locating.

Also, iFixit actually took one apart. They specifically mention the absence of a GPS chip.
 

LucidPsychosis

macrumors regular
Mar 6, 2010
177
0
Knoxville, TN
GPS is only in the 3G model. Incidentally, what part of east TN are you in? I live in Sevierville myself (soon to be Knoxville or Maryville when I go off to college).
 

Mark Booth

macrumors 68000
Jan 16, 2008
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I am not convinced it does not have gps. It is far too accurate.
See messages above. If you are connected to a known/mapped (by Skyhook) WiFi hotspot, it will be VERY accurate. Yes, this includes millions of WiFi networks in homes.

But now go down to Best Buy and purchase a brand new WiFi base station to replace your current WiFi base station. Oops... that new WiFi base station isn't in the Skyhook database so your iPad just got lost.

I'm glad you are "convinced". But that still doesn't make it true.

Mark
 

ImperialX

macrumors 65816
Jul 17, 2007
1,339
23
Tokyo, Japan
There is NO GPS in the iPad Wi-Fi. It's confirmed. It only triangulates your location via. Wi-Fi. Nothing special with that - the iPhone could do it.
 

Anonymous Freak

macrumors 603
Dec 12, 2002
5,120
432
Cascadia
To explain how WiFi triangulation works:

A van with a WiFi sniffer and a GPS unit drove around an area. It mapped out what WiFi signals (specifically the MAC addresses,) map to what GPS coordinates. This is the 'map' half. Skyhook is one company that does this, which happens to be the company Apple's Maps uses.

Later, a device with WiFi triangulation (original iPhone, iPod touch, iPad without 3G,) looks at the WiFi access point MAC addresses of the WiFi networks around it, and compares it to the database gathered by driving around. Voila. We have an approximate location.

As Mike Reed mentions, he is the only WiFi in his area. If the van has driven by his house, you will get a map location when you are near his house. But if he replaces his WiFi access point, you won't get any location, since the new access point has a different MAC address.

Also, if he moves, to somewhere where again, he is the only WiFi in his area, his *NEW* location will appear on a map as his old location; since the WiFi/GPS van won't have driven by either location yet. (For example, every once in a while, WiFi triangulation says I'm in Texas instead of Oregon, because my neighbor recently moved from Texas.)
 

Legolover64

macrumors regular
Feb 24, 2008
149
0
Does this technology work if I'm not on WiFi? Like, will I get Lat/Lon if I'm not on a network, but networks are available?

I'm more thn pleased with the iPad WiFi. I already paid for a 3G and own that (GPS works fine on there) and I want to save $130 for other stuff.
 

Mark Booth

macrumors 68000
Jan 16, 2008
1,617
436
Does this technology work if I'm not on WiFi? Like, will I get Lat/Lon if I'm not on a network, but networks are available?

I'm more thn pleased with the iPad WiFi. I already paid for a 3G and own that (GPS works fine on there) and I want to save $130 for other stuff.
Here's the problem.... For the WiFi-only iPad to communicate with Skyhook's database, the iPad has to have an internet connection. So, no, you won't get a Lat/Lon if you aren't on a network.

It's TWO parts that are needed for WiFi triangulation... 1) A "mapped" WiFi hotspot (a WiFi base station with a MAC address that is known to Skyhook), and, 2) A way for that information to be shared back and forth between the iPad and Skyhook.

Without an active WiFi connection, you can't achieve number 2.

Mark
 

Hmac

macrumors 68020
May 30, 2007
2,128
2
Midwest USA
TomTom app does not work on my iPad.
That's correct. It won't work on the wifi-only version of the iPad. It will work fine on the wifi+3G version that's being released later this month. This has been known since the iPad and its specs were announced.