How to manage devices in Amazon

http://www.amazon.com/gp/help/customer/display.html/ref=hp_rel_topic?ie=UTF8&nodeId=201252640

Go to Manage Your Kindle to manage your Kindle device or Kindle reading app. The names of your Kindle devices and reading apps appear in a list under Registered Kindles and Kindle Reading Apps.

1. Visit Manage Your Kindle 
2. Click Manage Your Devices. 
3. Click Edit next to the name of the device or application. 
4. Enter the desired name. 
5. Click Update.