Peek Nokia  

It's really great this product since 2008 until now still has millions of mobile subscribers. Both GSM or CDMA, and sold everything and we can type in a secret button on this phone. Ie;
1) To view IMEI (International Mobile Equipment Identity) by pressing the *#06#.
2) Seeing the software in it, including the date of manufacture and type of compression by pressing *#0000# or if it does not work *#9999#.
3) See the status of an existing call waiting by pressing *#43#.
4) Looking at private number which contact your phone by pressing *#30#.
5) Shows the number of phone transfers all calls by pressing *#21#.
6) See the caller's number on the transfer of the phone because you are not answered (call divert on) by pressing *#61#.
7) See the caller's number on the phone because the transfer out of range (call divert on) by pressing *#62#.
8) See the caller's number on the transfer because of busy phone (call divert on) by pressing *#67#.
9) Changing the operator logo, especially on the Nokia 3310 and 3330 type by pressing *#67705646#.
10) Displays the SIM clock status by pressing *#746025625#.
11) Switching to your phone profiles, the way is press the power button off without being held.
12) Changing the settings to the default Nokia mobile phone or manufacturer by pressing *#7780#.
13) Reseting phone timers and game scores by pressing *#73#.
14) See the status of call waiting by pressing *#43#.
15) see the factory code by pressing *#7760#.
16) Displays the serial number phone, date of manufacture, date of purchase, date of last repair, transfer of user data. To exit the phone must be reset again by pressing *#92702689#.
17) Seeing the phone security code by pressing *#2640#.
18) Viewing IP addresses hardware Blue-tooth by pressing *#2820#.
19) Activated the EFR with the best sound quality but the battery energy-intensive. To turn it off using the same code by pressing *#3370#.
20) Activated the EFR with the lowest sound quality but the battery energy-efficient. To turn it off using the same code by pressing *#4720#.
21) Towards the contents of phone book quickly on the phone by pressing the serial number and #, for example is 150#.
22) Divert calls to the targeted number for all calls by pressing **21*destination number#.
23) Divert calls to the destination number to call is not answered by pressing **61*destination number#.
24) Divert calls to the destination number to call when the phone was busy with pressing **67*destination number#.
25) Turn Screen: turn right *#5512#, turn left *#5513#, turn back *#5514#, and normal again *#5511#.

This only can I say, actually a lot that can be described in Nokia. Technology that will never cease in doing development.