All kinds of iPhone because the 3G, along with the iPad 3G and iPad 2 3G, include Assisted GPS (AGPS).

I've heard that isn't real GPS or that it is somehow inferior to real GPS. AGPS is really superior to real” GPS. However, techniques the iPhone is also inferior with a standalone navigational GPS being a Garmin or Tom Tom. I'm planning to explain the differences with shod and non-shod.

Positioning

The iPhone incorporates a regular GPS receiver, exactly like your standalone GPS. The assisted” part means the iPhone is able to get a quick lock depending on other data sources, like nearby cell phone towers or WiFi networks.

I'm not likely to try to write an explanation of this. There's a great article for this in Macworld by Glenn Fleishman, ” How the iPhone knows what your location is ,” which you should read. He's a journalist who focuses primarily on wireless technologies, and anything I could write on that subject would don't measure up to his writing.

But I can summarize that article for you personally in one paragraph, if you didn't bother to read it:

Because the iPhone includes a GPS radio which other data sources, it's quicker at finding your location than a standalone navigational GPS.

Your iPhone performs this without sacrificing final accuracy, but may offer you several approximations as you go along. (These are times an actual GPS would always be trying to figure out what your location is.) This is simplifying just a little; the iPhone has to conserve battery over your standalone GPS. If you're not actually using Maps or some other application that really needs pinpoint accuracy, it in all probability powers around the GPS and uses whatever radios it has powered as much as do approximate positioning instead of the most accurate positioning it's effective at. But when you need accurate positioning, it's there.

Maps

So why do people think the iPhone's GPS isn't a real GPS, It's because of the one way the iPhone is weaker than your standalone GPS. As shipped by Apple, the iPhone is entirely dependent for the Internet for map tile data.

That ensures that without a data signal, whether WiFi or 3G, the iPhone is not able to show you a map. You end up with a screen such as this:

From this, you could conclude that without having a data connection your iPhone isn't excellent as a navigational tool. You'd be right about that! But you could also conclude that this iPhone doesn't know where you stand. In fact, it knows where you are. It just neglects to put it on a roadmap, because it doesn't actually have a map from the area.

This is when standalone GPS devices are better. Because they don't hold the extra radios that this iPhone has, they can't download map data in the Internet. Instead, a standalone GPS includes map data about the device. Storing a whole country's (or even a complete continent's) map data takes a lot of space, therefore it is often rendered more crudely compared to the iPhone's maps.

Imagine drawing a map for a friend to get to your house. You know which road they'll be coming on, and also you know where they're attempting to go. You can complete the roads they have to pay attention to from memory, and mark turns and also the destination. This is how a standalone GPS works, with the exception that if it's up-to-date it knows all of the roads and will quickly draw everything quickly and to scale. It's rendered using just its memory, minus the aid of the 3G or WiFi network.

The iPhone's maps, for the other hand, are from your cloud. The iPhone basically asks to get a graphical map from your cloud, while using location and zoom it's enthusiastic about. The image the cloud returns could be beautifully rendered and completely up-to-date, but minus the cloud, the iPhone can't get anything.

But let's say your iPhone did have map data on device, Then it would be able to render maps without a data connection AND get a fix faster compared to a real standalone GPS. This is where the App Store is available in to play. Tom Tom and Garmin both sell apps offering map data. When running one of these apps, the iPhone will be able to find its location faster than a standalone GPS. However, even with no connection for the Internet, the app can provide a map.

Turn-by-turn navigation

If you've reached this aspect, you're probably wondering why the iPhone can't do turn-by-turn navigation. It's a fair question. The answer is complicated, but boils down simply: Apple will not provide the map data. Instead, Apple's map display uses data furnished by Google. And Google does not allow Apple to make use of that map data for turn-by-turn navigation. Apple, consequently, will not allow iPhone developers to submit turn-by-turn navigation apps that use the iPhone's map system.

So why can some Android phones provide turn-by-turn navigation, Google allows it.

This is the reason any turn-by-turn navigation app is planning to require its own map data, in lieu of working over cloud when it is available. There's been several hints that Apple may switch to their own data sooner or later, nevertheless it hasn't happened yet. Being dependent on a competitor thinking about keeping your device inferior isn't a good position to stay in, set up reasoning has nothing to do with competition.

Update: The next version of iOS 6 will switch the data source to Apple's. The iPhone will still download map data, but instead of downloading only a picture it will now download richer data which will allow it to display rotated maps more cleanly. And Apple is bringing turn-by-turn directions towards the iPhone 4S. The iPhone is not going to get offline navigational data, however.

Conclusion

The iPhone's GPS us very good. Without extra software, however, iPhone navigation is entirely influenced by the Internet. But you is able to see maps provided that the iPhone can attain the cloud. You can download software so you can see maps while away from your cloud. And any photo you're taking, even while away from your cloud, will nevertheless be tagged while using location in the iPhone.

The iPhone makes its connection for the cloud a strength, whereas standalone GPS units make the lack of a radio their strength. It's a complicated tradeoff. Saying the iPhone does not have real” GPS or that AGPS isn't real”, though, is inaccurate.

Author Steve Posted on