Skyhook's Wi-Fi Location Technology for iPhone/iPod touch

[MacRumors]

USAToday profiles Skyhook Wireless who helps provide some of the technology behind Apple's new GPS-like location features in the iPhone and iPod Touch's Google Maps application.

Skyhook Wireless was formed in 2003 and uses a database of Wi-Fi hotspots to determine your geographic location. The process is explained:

"Every Wi-Fi access point, whether public or private, sends out a signal every second or so, like a lighthouse. We pick up those signals and use our technology to calculate your exact location."

While Wi-Fi hotspots are detected based on these signals, no direct connection is made to them. To seed the system with data, Skyhook sent teams of drives around the US and Canada to map out hotspots. They say the have 70% of North America covered, and are currently adding Europe and Asia. Unlike GPS, Skyhook's system works better indoors and in urban settings.

Of interest, Skyhook generally receives a payment per device sold with the technology, and may be built into the fee Apple is charging for the iPod touch software update. For the iPhone, Apple starts with Skyhook's Wifi database first, and if unable to find a hotspot, it then falls back to using less-precise cellular tower information provided by Google.

A company called Navizon had provided very similar technology for iPhone users as an unofficial 3rd party application.


Article Link

[Yankees 4 Life]

that's pretty cool, thank goodness i didnt have to pay for my iphone update

[JDOG_]

Poor Navizon. Its entire product has casually been built-in to Google Maps and they're still charging for it.

[happydude]

Originally Posted by Yankees 4 Life

that's pretty cool, thank goodness i didnt have to pay for my iphone update

well, actually, since apple gets $20/month out of your AT&T plan . . . you are paying for the software update . . .

[pacohaas]

Poor Navizon. Its entire product has casually been built-in to Google Maps and they're still charging for it.

yeah and the 3rd-party program "Locate-me" does a better job at cell tower approximation anyway.

What I'm wondering is how exactly they are mapping the WiFi access points. Do they simply go by SSID or do they try to get the MAC address or something a little more identifiable?

example: Hey look, my home WiFi network is called "White House", I must be in Washington DC.

[phiberglass]

They don't go by name, they have all those wifi hotspots pinned everywhere, when you do get maps, it gets wifi/cellular towers around you, retrieves data from the company, then gives you an approximate location of where you are.

[emotion]

Interesting approach.

More info:
http://www.skyhookwireless.com/howitworks/

Coverage:
http://www.skyhookwireless.com/howitworks/coverage.php

[brendanryder]

but i still dont see how this is any help to ipod touch owners?
ok it sweet that they have this technology to use on maps but u have to have a wifi signal first before you can even load the map

[benspratling]

Wi-Fi based locations, are you kidding me?
I live in a college town, where lots of folks have WiFi base stations and lots of folks move around every year. The same day the location feature was released it was out of date. I got my location in my apartment where I've lived for three years with my own WiFi network, and it gave me error bounds of something like 30 or 50 feet to a location that was well over a mile away. Know why? Because it picked a WiFi network that used to be located where it said.
Oh, no, wait, I just bought an Apple Gigabit-Ethernet Airport base station two months ago, I guess I missed the boat. Besides, here the airport signal doesn't make it all the way out to the road, it's not like anyone who comes to visit me will ever really know where they are.

I'm hoping for a Tom Tom plug in GPS module.

On the other hand, this weekend, I was using the locate feature with the cell-phone network and although it gave me error bounds at something like a mile (I don't really know, because, of course, Maps has no scale!) I was easily able to find my location.

I think this WiFi location-based thing is a bad idea, but if they were putting it in the iPhone I guess they had to give iPod Touch users something so they could charge for Maps.

[pacohaas]

Originally Posted by brendanryder

but i still dont see how this is any help to ipod touch owners?
ok it sweet that they have this technology to use on maps but u have to have a wifi signal first before you can even load the map

haha, hadn't thought about that

[Hls811]

What I don't get is that it seems like you don't need to be connected to the various WiFi networks to get a read on where you are, but yet - it doesn't work like that. I'm in an area with 3 or 4 private access points (I can see them when I go into settings) - but yet it still won't "locate me" on my iPTouch.

"Every Wi-Fi access point, whether public or private, sends out a signal every second or so, like a lighthouse. We pick up those signals and use our technology to calculate your exact location."

[Rocketman]

So does it also capture newly identified wifi devices and report their position? The widespread adoption of mobile wifi devices is likely to confuse this system in the future unless mobile is somehow differentiated from fixed in serial numbers.

Rocketman

[indiekiduk]

Originally Posted by pacohaas

yeah and the 3rd-party program "Locate-me" does a better job at cell tower approximation anyway.

What I'm wondering is how exactly they are mapping the WiFi access points. Do they simply go by SSID or do they try to get the MAC address or something a little more identifiable?

example: Hey look, my home WiFi network is called "White House", I must be in Washington DC.

LOL, the locate-me app uses GOOGLE. The exact same as fw 1.1.3 Maps.

[indiekiduk]

Originally Posted by Rocketman

So does it also capture newly identified wifi devices and report their position? The widespread adoption of mobile wifi devices is likely to confuse this system in the future unless mobile is somehow differentiated from fixed in serial numbers.

Rocketman

Great point Rocketman. No it doesn't appear to. So although Skyhook might have good WiFi survey coverage right now, that'll change when everyone throws out their 802.11G router and buys an 802.11N, or sells them on ebay and the APs move all over the place. They will need to survey all over again which I think took them a few years. Where as Navizon is updated continually by the users (windows mobile that is) so has no risk of becomming out of date and accuracy improves over time.

[Lepton]

Here in the Long Island 'burbs, the locator can be accurate within 100 feet in one spot, and in another spot 500 feet away, it can be over a mile off. Here at my house it is about a mile and a half off. I wish I could add to the database by telling it the coordinates of WiFi spots I hang out near...

[roland.g]

I agree to how do they keep it current with new hot-spots showing up all the time.

Not sure how this really helps me as I expect that you are only taking advantage of the Skyhook location if you have your WiFi turned on. When I am using my iPhone, I only turn on the WiFi when I want to connect with it. Somehow I don't see myself doing this everytime I want to use Maps.

[b1wils1]

i've found that using cellular signals is more accurate in locating me. i've used several wifi spots, and they haven't been nearly as accurate.

an interesting thing with one of the wifi networks has also happened. i have a friend that when i'm at her place, i use my iphone on the network. she moved about a year ago, and now is several miles from where she used to live. when i used the locator on my iphone now, it still says that i'm in the location that my friend 'used' to live, so obviously skyhook must have driven and logged my friends wifi when she lived in her old place, placing that at probably a year ago.

it seems like this is a very inaccurate way to do this. does anyone else agree?
it just seems as if this will be dated VERY quickly.

[jfinke]

I would think that such a database would be out of date within 6 months. Cell phone towers don't move. People's wifi hotspots do. People move, turn them off, replace equipment, etc. They are basically attempting to do landmark recognition (go north of the tree with a crooked trunk) with moving landmarks.

[maverick808]

Originally Posted by roland.g

I agree to how do they keep it current with new hot-spots showing up all the time.

Not sure how this really helps me as I expect that you are only taking advantage of the Skyhook location if you have your WiFi turned on. When I am using my iPhone, I only turn on the WiFi when I want to connect with it. Somehow I don't see myself doing this everytime I want to use Maps.

Do you manually set wifi to off in settings? I don't see the point of doing this as it doesn't save that much battery life. Wifi will automatically turn off when you aren't interacting with the phone anyway.

[roland.g]

And Apple stock drops another $19.00

[robalan]

Hmmm, so this explains why my iPod Touch was able to locate me at home to within about 100 feet, despite the only Wi-Fi access point in range being my own Airport Extreme? I didn't expect it to work at all but instead it homed right in.

[MacNewbie03]

You can go to http://www.skyhookwireless.com/howitworks/coverage.php to see if your area is in Skyhook's database. I would guess that the reason your location may be off is skyhook's database isn't real time

[pacohaas]

Originally Posted by indiekiduk

LOL, the locate-me app uses GOOGLE. The exact same as fw 1.1.3 Maps.

Which explains why it works better than Navizon, which is what I was saying.

[happydude]

Originally Posted by b1wils1

i've found that using cellular signals is more accurate in locating me. i've used several wifi spots, and they haven't been nearly as accurate.

an interesting thing with one of the wifi networks has also happened. i have a friend that when i'm at her place, i use my iphone on the network. she moved about a year ago, and now is several miles from where she used to live. when i used the locator on my iphone now, it still says that i'm in the location that my friend 'used' to live, so obviously skyhook must have driven and logged my friends wifi when she lived in her old place, placing that at probably a year ago.

it seems like this is a very inaccurate way to do this. does anyone else agree?
it just seems as if this will be dated VERY quickly.

given your example, it already is dated. this seems like something apple would have caught on to before implementing it. i don't know if this is why they did it, but i'm afraid they're starting to cram in applications just to say they have it vs. testing it out 100% to make sure it is worth having. obviously, as many people have been writing, the locate me already has issues and it will just grow worse every day unless skyhook routinely does updates. and if it took them a couple years to get 70% of the nation mapped, how long is it going to be before the next update? i'm disappointed in apple over this one, they should have known this would be an issue. hoepfully the SDK release will give garmin or tomtom or some "real" GPS company an opportunity to fill this hole left by apple!

[laughingboy]

Originally Posted by jfinke

I would think that such a database would be out of date within 6 months. Cell phone towers don't move. People's wifi hotspots do. People move, turn them off, replace equipment, etc. They are basically attempting to do landmark recognition (go north of the tree with a crooked trunk) with moving landmarks.

I believe that one of the features of this service is database updates from results of location queries. I'm guessing that this is part of their model - once they have a decent starting point, users will keep the data fresh merely by using the service.

From Skyhook's website

Skyhook maintains the accuracy of the access point reference database through an ongoing and continuous data monitoring, analysis and collection process. The two main main components are:

1. Automated Self-Healing Network
Each WPS location transaction is initiated with a scan for nearby access points. The resulting access point information is then compared against the central reference network. Known access points (those already in the reference network) are used to calculate the location of the device.

Any access point that is either not in the database or was previously associated with a different geographic location is automatically identified and recorded to the new corresponding calculated location. In this manner, WPS automatically fixes and expands the reference network as it is being used.