I'm curious if keypad commands like those listed below come from the Android OS or if they're added by manufacturers. On my N1, I know of these two commands:
*#*#checkin#*#* - Phones home to check for updates.
*#*#info#*#* - Enters a detailed phone information menu.
Topic dialer-codes android
Category Android
There are many that seem to be "standard", but they can also be added by individual applications (e.g. provider-installed).
Check out http://forum.xda-developers.com/showthread.php?t=540483 for a method to extract telephony codes from your installed apps.
It's android based, I tried same commands on Moto Droid and HTC myTouch, both worked exactly the same.
I entered ##info## on my Captivate and got to the same menu.
So, in the interest of adding to the list
*#*#1472365#*#* gets you to the GPS configuration menu (not sure what word that works out to)
Geeks Mental is a community that publishes articles and tutorials about Web, Android, Data Science, new techniques and Linux security.