No man is an island no man stands alone". We human beings can't live without friends. Friends are the real asset of our life. So its become very important for us to keep a track of them and even mark our presence in there life. So wherever you go just take a picture of it and add it to your checkins list. Also post a comment about it to your FaceBook account. Your friends can now see where you have been. So in this way you can locate your Buddies without missing anything of there life.
Access fine location sources such as the Global Positioning System on the phone, where available. Malicious applications can use this to determine where you are, and may consume additional battery power.
coarse (network-based) location
Access coarse location sources such as the cellular network database to determine an approximate phone location, where available. Malicious applications can use this to determine approximately where you are.