Tip 1 : Do u know how to use the edit button (abc or  pencil button)?
Heres how... in the inbox for example; u wanna delete multiple sms, simply hold  the edit button, scroll down, and then, press c to delete the marked sms. The  edit button can also b used to copy and past text in sms, simply hold it and  scroll across, choose copy. pretty good for placing song names in ngages 

Tip 2 : Shit happens, on a smartphone, its inevitable  u do something wrong, and tis calls for a format of fone. to format the fone,  press *#7370#, then enter the lock code, which is the sec code of the fone.  NOTE: batt must b full, else if format is disrupted by low batt, consequences  will b disatrous
I heard the code *#7780# works too, pretty much the same i tink.

for 6600 users, to format the fone, theres an  alternative way. Press and hold <3>, <*>, and the buttons, then power on fone,  keep holding on the 3 buttons, till u come to a format screen. tis method ONLY  works on 6600, and need not enter the sec code. BUT sec code wun be reset to  default 12345.

Tip 3 : TO NGAGE USERS; Did u know u can install .sis files simply using the  cable given? Juz plug it in, place the .sis file anywhere on e: (the mmc), not  in any folders, root of e:, disconnect, then look for it in manager.

Tip 4: Save on battery and system memory being used by  regulary checking the task manager which can be accessed by holding down the  menu button!!

Tip 5: Type *#06# to display your IMEI serial number, very valuable for the  unlocking your phone to other sim cards

Tip 6: Type *#0000# to view which firmware version you  are running

Tip 4a: Set the screen saver to a short time out  period to prolong battery life.
Tip 4b: Avoid restarting the phone, or repeatedly turning it on and off. This  helps increase battery life.

Tip 7: If you would like to avoid being "blue jacked",  keep bluetooth turned off, or set your phone's visibility to hidden.

Tip 8: Don't want to carry a watch and a phone? Set  the screen saver to show date and time, then you can ditch the watch.

Tip 9: Save memory when installing apps, by installing over bluetooth. This  can be done using the nokia phone suite and a bluetooth serial connection. Only  works with .SIS files, so java still has to be sent to the phone, but will save  space when using .SIS files.

Tip 10: Operator logos
Use a filemanager like FExplorer or SeleQ to add the folders:  "c:/system/Apps/phone/oplogo". Add a .bmp picture to folder "oplogo" and restart  your phone! The .bmp picture size needs to be: 97 x 25 pixels