GPS and iPad Wi - Fi + Cellular

Early January 2011 I wrote started the year in a bad mood (¹) After finding repeated incompetence of Apple sellers, during Christmas, concerning devices they sold, mainly iPad and iPhone. I note unfortunately as 5 years later, nothing has changed, it is to despair !

I don't know in what language to write it, but this unacceptable breach of their products even today causes the disbelief of new clients regarding the presence of a true GPS on these mobile devices. I just have recently to experience it with a boater who argued me, I quote :

" It is an error to say that the Cellular iPad integrates a "GPS chip"., It is only a chip that makes a triangulation by GSM antennas..
Source : verified by myself _and_ confirmed by APPLE. "

And to clarify, in response to my strong denials :

"When I said that it had been confirmed to me by Apple., It is not the "Apple sellers in the store" but from Apple support by phone with a guy who searched in their internal database . "

I do not know who writes these "internal database" but Apple support should have the obligation to read the articles in web sites iFixit up to Chipworks to learn what lies under the hood of their mobile.

iPad Wi - Fi against iPad Wi - Fi + Cellular

These two models, the first, iPad Wi-Fi, only has Wi-Fi as a means of network connection, and the location is only provided by geo-referenced Wi-Fi hotspots (²), so very inaccurate.

The second model, called the iPad Wi-Fi+Cellular, provides access to 3G/4G cellular network with a SIM card and an appropriate subscription (as for an iPhone). It is featured with a modem processor designed by Qualcomm (MDM96x5M series), incorporating one assisted A - GPS receiver (Qualcomm IZat Gen8C), to which is added an inertial 3-axis sensor and 3-axis accelerometer, all providing extremely accurate positioning of the mobile, serving navigation mapping for car , marine or air applications. Localization can be obtained by alternately access points Wi-Fi, by cellular antennas trilateration, or built-in GPS. The A-GPS receiver is compatible with the American GPS, Russian GLONASS systems, and soon GALILEO (³).

About iPhone, they all are featured with such processor with built-in assisted GPS modem. It has therefore not to make a choice.

iPad Wi-Fi + Cellular

With the risk of repeating, once again, GPS location doesn't absolutely need the cellular network to work, a SIM card and a subscription to this network are therefore absolutely UN-NE-CES-SA-RY. The A-GPS chip built into this model (as to the iPhone) is perfectly capable of acquiring satellites in the GPS constellation without the assistance (the 'A' of A-GPS) by the cellular network. This assistance provides only an acceleration of the achievement of location, or accelerated location recovery if lost after passing through a tunnel, in example, through the connection on a dedicated server providing real-time ephemeris of the satellite constellation. This is particularly important on the road use. Without this assistance the receiver GPS works independently like any other GPS receiver, marine or outdoor.

In conclusion, to twist the neck of the erroneous information disclosed by Apple resellers, an iPad Wi-Fi + Cellular, as an iPhone, is able to locate yourself anywhere on the globe, in the middle of the Pacific Ocean and the Sahara desert, or in an aircraft at 9000 metres above sea level (⁴), with no access to the internet network.

Please repost widely !

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(¹) iPad , GPS and 3G cellular network subscription
(²) How the iPhone knows where you are
(³) Qualcomm Announces Broad Support for Galileo Across Snapdragon Processor and Modem Portfolios
(⁴) iPad GPS far away from networks
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