Custom Map iPhone

I trying to figure out how to create a Custom Map like the following:

h开发者_高级运维ttp://itunes.apple.com/us/app/mall-book-california/id342584415?mt=8

http://www.macworld.com/appguide/app.html?id=541350&expand=false

I just don't know where to start from, do I use UIWebView or MapKit? Any help will be appreciated.

Thanks

What we did in our app is use a UIImageView on a UIScrollView. You need to take a screenshot of the object you will map on the google-map and precisely draw your overlay over it. Also you need to take the top left coordinate and bottom right coordinate of the screenshot you took from the map. Then put the overlay image inside an imageview, image view on scrollview, and scale your coordinate system on the scrollview with the coordinates you took from the map. Now you can precisely plot POI-s on your overlay. A note: The first thing we did is we overlaid the g-map with custom image view but it was really slow when scrolled, so don't even try it. Good luck with coding.

[EDIT] you take a large screenshot of an area on google map like this http://www.metacafe.com/watch/1073912/google_maps_hack_how_to_save_large_maps/