Does the iPad have a “real GPS” in it?
Google the phrase “does the iPad have a GPS” and prepare to be overwhelmed. More than five years after the iPad was introduced, lots of people are still confused about whether the tablet actually has a GPS in it. And if it does have a GPS, is it a “real” one? Let’s bust some myths and settle the issue once and for all.
Is it a “real” GPS?
First, some simple facts. Every iPad ever made has both WiFi and Bluetooth, two wireless technologies for connecting to nearby devices (in the case of Bluetooth) and the internet (in the case of WiFi). The only additional option is to add cellular service, originally called 3G and now called LTE for the latest models. This cellular option allows the iPad to connect to the internet anywhere your cell phone works, so if you want to check your email while driving down the interstate, you can do that (but it won’t work in flight).
There’s more to the story, though. In addition to the cellular radio, the 3G/LTE models of the iPad also have a built-in GPS receiver. Apple calls this “assisted GPS,” which is probably where the confusion comes in. By assisted GPS, Apple means that the GPS receiver in the iPad can use nearby cell towers to provide a faster position lock (what engineers call “time to first fix”). Instead of starting up cold and searching for satellites, which can take up to a few minutes in some cases, the iPad knows right where to look. With a hot start like this, your iPad can find its position in just seconds.
This is a handy feature if you’re trying to find your location on a map, especially if you’re in a big city where buildings can block GPS reception. But it’s important to note that the iPad does not require the cellular connection. In fact, you can purchase a 3G/LTE iPad, never sign up for service with Verizon or AT&T and still get very good GPS performance. If you want to test this, go to the Settings app and turn off Cellular Data, Bluetooth and WiFi. Even with all of its wireless radios off, the iPad will still show your position on ForeFlight or Garmin Pilot (again, assuming it’s a 3G/LTE model). And once you’re flying, your iPad will have an excellent view of the sky and should maintain good GPS accuracy.
So “assisted GPS,” far from being a cheap version of GPS or an Apple marketing line, is actually a good thing. By using all the other sensors on the iPad, the GPS performance is improved. Make no mistake: the 3G/LTE iPad has a real GPS built-in.
If you have a WiFi-only iPad, or if you want a backup for your 3G/LTE iPad, here are our tips for buying an external GPS.
I use my iPad all the time for flying and only use the internal GPS that comes with it when you have the cellular radio. It is very accurate and I have rarely had it lose a signal
Duh! What a worthless article. Make sure to read the next publication on calculus where it describes that 1 + 1 = 2!
It may be obvious to you, George, but based on the emails we receive a lot of pilots are failing calculus!
Thank you for this article. Having been to two Apple Stores and found the assistants didn’t know what was in their devices – perhaps they need a maths education too.. I am now more reassured to know which device to purchase and that it will function without the need for an external GPS receiver. Thanks Sporty.
Any article on the pros/cons of the different software products i.e Garmin/ForeFlight etc?
Interesting article, however the question is not explicitly answered. In my simple naive mind, “real” GPS comes from satellites. Does the iPad have a GPS receiver? I’ve heard some folks refer to cell tower locating as LPS (local positioning system). While this is a valuable feature, it’s not the same thing as GPS. I’ve also heard that many cellular base infrastructure features are available before a call is placed, which are also available if you don’t have an account. This could include LPS.
I’m curious about all this because i wonder if I buy some maritime navigation software, will it work several miles offshore?
Yes to both questions. I have a friend that got an iPad mini with LTE and used it for sailing recently.
Third paragraph: “…the 3G/LTE models of the iPad also have a built-in GPS receiver.”
Excellent, thanks Eric for clarifications. I also found another article with similar comments (http://pacificsailors.com/2012/04/ipad-on-board.html), although not a technical article about iPads.
My confusion is from the following sentence “…the 3G/LTE models of the iPad also have a built-in GPS receiver. Apple calls this ‘assisted GPS,'”. I’m still thinking ‘assisted GPS’ is not real GPS, so maybe the case is that the iPad has two additional built-in receivers? Or maybe I’m trying to get too much out of these terms. : )
Assisted GPS (A-GPS) is the most real GPS you can get.
Without the network, A-GPS works like a normal GPS.
When on the network, A-GPS actually downloads the satellite orbit data from the Internet. Like written in the article, this data needs your macro position. Network data is used to make the macro positioning first.
HOwever, the thing is to use your 4G/3G data for downloading the orbit data from server. This data is fresh for multiple days, and e.g. Nokia used to operate these servers. Downloaded orbit data speeds up considerably the actual positioning.
The orbit data downloaded from the satellite comes veeery slow. This is why “real GPS” waits for 30…60 seconds for fix, unless used very frequently.
The actual clock data (“my time is here high above”) comes down fast and frequent. This is why positioning takes 1-3 seconds after orbit data is acquired.
So in short, you could call A-GPS as GPS Turbo.
Is it like the GPSs that I’ve heard in cars that tell you where to turn each step of the way? Thank you!