Android power user codes

*#*#4636#*#*
This code shows following 4 menus on screen:
Phone information
Battery information
Battery history
Usage statistics

*#*#7594#*#*
This code can be used to change the "End Call / Power" button action in your phone.

*#*#273283*255*663282*#*#*
This code opens a File copy screen where you can backup your media files e.g. Images, Sound, Video and Voice memo.

*#*#197328640#*#*
This code can be used to enter into Service mode. You can run various tests and change settings in the service mode.

WLAN, GPS and Bluetooth Test Codes:
*#*#232339#*#* OR *#*#526#*#* OR *#*#528#*#* - WLAN test (Use "Menu" button to start various tests)
*#*#232338#*#* - Shows WiFi MAC address
*#*#1472365#*#* - GPS test
*#*#1575#*#* - Another GPS test
*#*#232331#*#* - Bluetooth test
*#*#232337#*# - Shows Bluetooth device address

*#*#8255#*#*
This code can be used to launch GTalk Service Monitor.

Codes to get Firmware version information:
*#*#4986*2650468#*#* - PDA, Phone, H/W, RFCallDate
*#*#1234#*#* - PDA and Phone
*#*#1111#*#* - FTA SW Version
*#*#2222#*#* - FTA HW Version
*#*#44336#*#* - PDA, Phone, CSC, Build Time, Changelist number

Codes to launch various Factory Tests:
*#*#0283#*#* - Packet Loopback
*#*#0*#*#* - LCD test
*#*#0673#*#* OR *#*#0289#*#* - Melody test
*#*#0842#*#* - Device test (Vibration test and BackLight test)
*#*#2663#*#* - Touch screen version
*#*#2664#*#* - Touch screen test
*#*#0588#*#* - Proximity sensor test
*#*#3264#*#* - RAM version

More codes (factory reset etc)