# iPad GPS without data plan OR wi-fi...how? **URL:** \ **Category:** Factual Questions\ **Created:** [March 3, 2012, 10:56pm UTC](https://boards.straightdope.com/t/ipad-gps-without-data-plan-or-wi-fi-how/614683 "2012-03-03T22:56:34Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Stoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/stoid/32/272_2.png) [@Stoid](https://boards.straightdope.com/u/Stoid)\ **Post date:** [March 3, 2012, 10:56pm UTC](https://boards.straightdope.com/t/ipad-gps-without-data-plan-or-wi-fi-how/614683/1 "2012-03-03T22:56:34Z")
I have been trying to get a definitive answer to this and there’s too much conflicting stuff out there. I have a 3g iPad, but no data plan and no sim. I just turned off my wifi and went to maps and it didn’t fail to locate me, it just said it would do it BETTER if I had my wi-fi turned on. So, this is what I am trying to understand: If I had an iPad that was “wifi-only” would it be completely incapable of receiving GPS data at all, or would it be limited to doing so with wi-fi turned on, or limited to doing so with wi-fi turned on **and** some app that somehow communicates with satellites? In other words, is there something in the iPad 3g model’s hardware that has nothing to do with its 3g capability that allows it to communicate with GPS satellites, and is that hardware missing from wifi-only models? ---
**Author:** ![Pork\_Rind](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pork_rind/32/111_2.png) [@Pork\_Rind](https://boards.straightdope.com/u/Pork_Rind)\ **Post date:** [March 3, 2012, 11:03pm UTC](https://boards.straightdope.com/t/ipad-gps-without-data-plan-or-wi-fi-how/614683/2 "2012-03-03T23:03:25Z")
> [@Stoid](#): > > In other words, is there something in the iPad 3g model’s hardware that has nothing to do with its 3g capability that allows it to communicate with GPS satellites, and is that hardware missing from wifi-only models? Yes. The 3G iPads all have a dedicated gps receiver. The wifi-only iPads do not. ---
**Author:** ![tellyworth](https://avatars.discourse-cdn.com/v4/letter/t/977dab/32.png) [@tellyworth](https://boards.straightdope.com/u/tellyworth)\ **Post date:** [March 3, 2012, 11:20pm UTC](https://boards.straightdope.com/t/ipad-gps-without-data-plan-or-wi-fi-how/614683/3 "2012-03-03T23:20:08Z")
> **[Assisted GNSS](https://en.wikipedia.org/wiki/Assisted_GPS)** > > Assisted GNSS (A-GNSS) is a GNSS augmentation system that often significantly improves the startup performance—i.e., time-to-first-fix (TTFF)—of a global navigation satellite system (GNSS). A-GNSS works by providing the necessary data to the device via a radio network instead of the slow satellite link, essentially "warming up" the receiver for a fix. When applied to GPS, it is known as assisted GPS or augmented GPS (abbreviated generally as A-GPS and less commonly as aGPS). Other local names inc... > **[Wi-Fi positioning system](https://en.wikipedia.org/wiki/Wi-Fi_Positioning_System)** > > Wi-Fi positioning system (WPS, also abbreviated as WiPS or WFPS) is a geolocation system that uses the characteristics of nearby Wi-Fi hotspots and other wireless access points to discover where a device is located. > It is used where satellite navigation such as GPS is inadequate due to various causes including multipath and signal blockage indoors, or where acquiring a satellite fix would take too long. Such systems include assisted GPS, urban positioning services through hotspot databases, an... Your 3g ipad uses real GPS hardware in conjunction with wifi positioning. Non-3g models use only wifi positioning. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 3, 2012, 11:25pm UTC](https://boards.straightdope.com/t/ipad-gps-without-data-plan-or-wi-fi-how/614683/4 "2012-03-03T23:25:54Z")
The rationale presumably being that the Wi-Fi models will be used indoors, or otherwise not generally moving about much? ---
**Author:** ![pipper](https://avatars.discourse-cdn.com/v4/letter/p/c2a13f/32.png) [@pipper](https://boards.straightdope.com/u/pipper)\ **Post date:** [March 3, 2012, 11:34pm UTC](https://boards.straightdope.com/t/ipad-gps-without-data-plan-or-wi-fi-how/614683/5 "2012-03-03T23:34:59Z")
I think it’s more a hardware issue. The same sub-circuit board that houses the 3G receiver also has a gps chip on it. No 3G, no gps chip. I use my iPad for offline navigation quite a bit so I got the 3G model just for the gps functionality. I have never turned on the 3G. ---
**Author:** ![Stoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/stoid/32/272_2.png) [@Stoid](https://boards.straightdope.com/u/Stoid)\ **Post date:** [March 3, 2012, 11:38pm UTC](https://boards.straightdope.com/t/ipad-gps-without-data-plan-or-wi-fi-how/614683/6 "2012-03-03T23:38:32Z")
Just as an aside, I have to say that GPS blows my mind. On my iPhone I have an app that tracks me for the purposes of exercise, and the precision is astonishing. I walked down to the local 7-11 one day, and it’s a small one, and for some reason I was going back and forth in the aisles looking for something. When I looked at my route, _ **every single step** _ I had taken inside the 7-11 had registered, with lines going up and back and criss-crossing in this tight little area inside the 7-11. It’s a sci-fi kinda world… ---
**Author:** ![xash](https://avatars.discourse-cdn.com/v4/letter/x/c6cbf5/32.png) [@xash](https://boards.straightdope.com/u/xash)\ **Post date:** [March 3, 2012, 11:59pm UTC](https://boards.straightdope.com/t/ipad-gps-without-data-plan-or-wi-fi-how/614683/7 "2012-03-03T23:59:15Z")
WiFi plus 3G model: has GPS hardware (assumed to be integrated with the cellular radio) does not need 3G data or WiFi to be on to get a GPS fix, because the GPS hardware will communicate directly with GPS sattellites (i.e. no data connection needed) even though it will accurately calculate its location with 3G/WiFi data OFF, it still needs data in order to show you the location in the Maps app, unless map data for that location was previously cached (or you use an offline maps app such as TomTom) With 3G radio on, it also uses A-GPS to triangulate cellular towers in order to figure out location and get a quicker fix on the sattelites through the GPS hardware With WiFi on, it also uses WiFi triangulation WiFi only model: does not have GPS hardware With WiFi OFF it will only show you last known location With WiFi ON it will use WiFi triangulation to show you location (this uses a data connection to query a database of known WiFi access points) WiFi triangulation has nothing to do with GPS satellites. It uses a database of know WiFi hotspots and their known locations instead. They collect this data in the same manner Google maps vehicles do; drive around neighborhoods. Apple used to use a 3rd party ([www.skyhook.com](http://www.skyhook.com)), but now has its own database.