Android secret codes
Some 'secret' codes are Android system codes, and usually begin with an asterisk or a pound symbol/hashtag. These don't require you to be connected to a network to use them, since they're just for the Android system on your device. These codes are updated regularly as new versions of Android software are released, and some manufacturers have their own additional special codes.The code entry procedure is very simple and only requires you to bring up your dialer keypad and enter the appropriate number sequence. It's important to note that some codes are carrier-specific, so they won't work on all devices. So if your phone doesn't respond to a code, don't dwell on it, just move on and find another one.
Warning! These codes should be used with caution. They can make your phone lose data, or render it unusable. There's a lot of incomprehensible tech jargon which pops up in the menus after entering some of these codes, which means that if you aren't 100 percent sure what you're doing, don't do it.
List of secret codes for Android
*Info codes*
*#06# Show phone's IMEI
*#0*# Info menu (doesn't work for all phones)
*#*#4636#*#* Info menu
*#*#34971539#*#* Camera info
*#*#1111#*#* FTA software version
*#*#1234#*#* PDA software version
*#12580*369# Software and hardware info
*#7465625# Device lock status
*#*#232338#*#* MAC address
*#*#2663#*#* Touchscreen version
*#*#3264#*#* RAM version
*#*#232337#*# Bluetooth address
*#*#2222#*#* Hardware version
*#*#44336#*#* Software version and update info
Backup codes
*#*#273282*255*663282*#*#* Backup all media
Testing codes
*#*#197328640#*#* Test mode
*#*#232339#*#* Wi-Fi test
*#*#0842#*#* Brightness and vibration test
*#*#2664#*#* Touchscreen test
*#*#232331#*#* Bluetooth test
*#*#7262626#*#* Field test
*#*#1472365#*#* GPS quick test
*#*#1575#*#* Full GPS test
*#*#0283#*#* Packet loopback test
*#*#0*#*#* LCD display test
*#*#0289#*#* Audio test
*#*#0588#*#* Proximity sensor test
Configuration codes
*#9090# Diagnostics settings
*#301279# HSDPA/HSUPA settings
*#872564# USB logging settings
Developer codes
*#9900# System dump mode
##778 (+green/call button) EPST menu
Other codes
*#7780# (Caution!) Factory reset
*2767*3855# (Caution!) Full factory reset
*#*#7594#*#* Power off the phone
*#*#8351#*#* Activate dialer log mode
#*#8350#*#* Deactivate dialer log mode