On Android it often depends on the specific model you have. Here are some for the Samsung S3:
#06# Show IMEI number
#0# LCD Test Menu
##4636##* user statistics and Phone Info
#0011# Displays status information for the GSM
#1234# View SW Version PDA, CSC, MODEM
#12580369# SW & HW Info
#197328640# Service Mode
#32489# (Ciphering Info)
#232337# Bluetooth Address
#232331# Bluetooth Test Mode
#232338# WLAN MAC Address
#232339# WLAN Test Mode
#0842# Vibra Motor Test Mode
#0782# Real Time Clock Test
#0673# Audio Test Mode
#0# General Test Mode
#2263# RF Band Selection
#872564# USB Logging Control
#4238378# GCF Configuration
#0283# Audio Loopback Control
#1575# GPS Control Menu
#3214789650# LBS Test Mode
#44336# Sofware Version Info
#7780# Factory Reset
27673855# Full Factory Reset
#0289# Melody Test Mode
#2663# TSP / TSK firmware update
#03# NAND Flash S/N
#0589# Light Sensor Test Mode
#0588# Proximity Sensor Test
#3282727336# Data Usage Status
#7594# Remap Shutdown to End Call TSK
#34971539# Camera Firmware
#528# WLAN Engineering Mode
#7412365# Camera Firmware Menu
#07# Test History
#3214789# GCF Mode Status
#272886# Auto Answer Selection
#8736364# OTA Update Menu
#301279# HSDPA/HSUPA Control Menu
#7353# Quick Test Menu
27674387264636# Sellout SMS / PCODE view
#7465625# View Phone Lock Status
7465625638# Configure Network Lock MCC/MNC
#7465625638# Insert Network Lock Keycode
##7780##* Factory data reset - Clears Google-account data, system and program settings and installed programs. system will not be deleted, and OEM programs, as well as My Documents (pictures, music, videos)
On iPhones, try 3001#12345# .
On Android it often depends on the specific model you have. Here are some for the Samsung S3:
#06# Show IMEI number
#0# LCD Test Menu
##4636##* user statistics and Phone Info
#0011# Displays status information for the GSM
#1234# View SW Version PDA, CSC, MODEM
#12580369# SW & HW Info
#197328640# Service Mode
#32489# (Ciphering Info)
#232337# Bluetooth Address
#232331# Bluetooth Test Mode
#232338# WLAN MAC Address
#232339# WLAN Test Mode
#0842# Vibra Motor Test Mode
#0782# Real Time Clock Test
#0673# Audio Test Mode
#0# General Test Mode
#2263# RF Band Selection
#872564# USB Logging Control
#4238378# GCF Configuration
#0283# Audio Loopback Control
#1575# GPS Control Menu
#3214789650# LBS Test Mode
#44336# Sofware Version Info
#7780# Factory Reset
27673855# Full Factory Reset
#0289# Melody Test Mode
#2663# TSP / TSK firmware update
#03# NAND Flash S/N
#0589# Light Sensor Test Mode
#0588# Proximity Sensor Test
#3282727336# Data Usage Status
#7594# Remap Shutdown to End Call TSK
#34971539# Camera Firmware
#528# WLAN Engineering Mode
#7412365# Camera Firmware Menu
#07# Test History
#3214789# GCF Mode Status
#272886# Auto Answer Selection
#8736364# OTA Update Menu
#301279# HSDPA/HSUPA Control Menu
#7353# Quick Test Menu
27674387264636# Sellout SMS / PCODE view
#7465625# View Phone Lock Status
7465625638# Configure Network Lock MCC/MNC
#7465625638# Insert Network Lock Keycode
##7780##* Factory data reset - Clears Google-account data, system and program settings and installed programs. system will not be deleted, and OEM programs, as well as My Documents (pictures, music, videos)