The iPhone’s Map Annotation Callouts are very useful for displaying small amounts of information when a map pin (annotation) is selected. One problem with the standard callouts present in iOS is the inability to change the height of the callout. For example, you may want to display a logo or other image that is taller than the default callout. Or you may want to display an address and phone number on separate lines under the title. Both of these scenarios are impossible using the standard iOS callouts.
There are many steps to building a good replacement callout with the proper look and behavior, but it can be done.
Part 2 covers adding a button to the custom callout, which is not as simple as it sounds.