Q:

How to display a map by mapkit framework in iphone using URL like http://maps.google.com....[it opens map as new App]

When we open : http://maps.google.com & type :  category:"motel"+California+USA we get the California region map with the motels in that region. This is done by using MapsApp in iphone. But it closes the current application & opens the map as New App. 
Now is it possible to do the same thing with mapkit framework? How to use URL in Mapkit like 
http://maps.google.com?q=category....

A:

Add an MKMapView to your application. Take a look at "Specifying the Visible Map Region" to center it on California. 
As for showing motels, you would have to handle that manually. You could use a service to find the hotels and then add them to your MKMapView as MKAnnotations.

