<p>The <a href="http://developer.apple.com/documentation/AppleApplications/Reference/SafariWebContent/UsingiPhoneApplications/chapter_6_section_4.html" rel="nofollow noreferrer">Apple Developer Documentation</a> (link is dead now) explains that if you place a link in a web page and then click it whilst using Mobile Safari on the iPhone, the Google Maps application that is provided as standard with the iPhone will launch.</p>

<p>How can I launch the same Google Maps application with a specific address from within my own native iPhone application (i.e. not a web page through Mobile Safari) in the same way that tapping an address in Contacts launches the map?</p>

<p><strong>NOTE:  THIS ONLY WORKS ON THE DEVICE ITSELF.  NOT IN THE SIMULATOR.</strong></p>

For iOS 5.1.1 and lower, use the
```
openURL
```
method of
```
UIApplication
```
. It will perform the normal iPhone magical URL reinterpretation. so
```
```
[someUIApplication openURL:[NSURL URLWithString:@"http://maps.google.com/maps?q=London"]]
```
```
should invoke the Google maps app.
From iOS 6, you'll be invoking Apple's own Maps app. For this, configure an
```
MKMapItem
```
object with the location you want to display, and then send it the
```
openInMapsWithLaunchOptions
```
message. To start at the current location, try:
```
```
[[MKMapItem mapItemForCurrentLocation] openInMapsWithLaunchOptions:nil];
```
```
You'll need to be linked against MapKit for this (and it will prompt for location access, I believe).