hereX koko app for iPhone and iPad

You can share the current locations and tracks of your friends up to 4 by Apple remote Notification service. it is convenient for meeting your friends, because you can see the current locations of your friends in real time. You can select the sending interval from 15sec, 30sec or 60sec. Your friends iPhone can be registerd via Bluetooth or e-mail. you can define the group of the friend.
Your current locations can be saved and sent to the friends in the background. But the current locations of friends can not be recieved in the background.
Notes:Please pay attention to the remaining amount of the battery. Continued use of GPS running in the background can dramatically decrease battery life in similar to foreground.