Map on Android

A simple example:
http://developer.android.com/resources/tutorials/views/hello-mapview.html

About Drop a Pin to map:
http://stackoverflow.com/questions/6545027/how-to-drop-a-pin-on-google-map-and-how-to-get-current-address-in-dialog-box-on
http://stackoverflow.com/questions/3636702/how-do-i-drop-spots-on-google-map-in-an-android-app
http://stackoverflow.com/questions/2683287/drop-pin-on-default-google-maps-from-my-app-in-android

Find a location
http://androidcookbook.com/Recipe.seam?recipeId=1454

Find MD5 of my key:
keytool -list -keystore /Users/noguxun/.android/debug.keystore -alias androiddebugkey
The password is "android".

Sign the key:
http://code.google.com/android/maps-api-signup.html

Good Tutorial:
http://www.vogella.de/articles/AndroidLocationAPI/article.html

Distance:
http://stackoverflow.com/questions/3759680/android-how-to-detect-if-users-if-within-distance-of-geopoint-on-mapview
http://stackoverflow.com/questions/6283028/distance-of-two-geo-point-android