Nokia 6131

The Nokia 6131/Nokia 6133 is a Nokia clamshell phone released in February 2006.
The model is part of the Base Band 5 series phones, which are more difficult to unlock compared to previous Nokia phones.
Features:-
Features include a 1.3 megapixel digital camera, support for up to a two-gigabyte microSD Card, 240x320 QVGA screen with 16.7 million colors and external 128x160 TFT screen with 262,144 colors. Software includes an XHTML compatible web browser, an email client and a media player (mp3, mp4 (audio only) & 3GP supported). There is also a small button located on the top right side of the phone, that when pushed, flips the phone open.
The phone is very customizable. Users can manage many of the phones features in the Nokia PC Suite. Themes may also be downloaded onto the phone, changing the menus, icons, colors, etc. Other customizable aspects of the Nokia 6126 include adding MP3 files to the phone, and using those files as ringtones, without the need of converting them to WMA format. There is also a setting used for the screen saver on the external screen of the phone that allows a slide show of images the user has taken with the phones camera.
This phone is known for its outstanding features, one in a million, however many get annoyed at the fact that unlocking is a pain even though it is free for anyone to unlock using the code 123456654321 and calling it. Many people that are running on mobile over internet, (VOIP) or WLAN have this problem.
Veriants:-

1.6126: North American version of the 6131 (released for AT&T and Fido_Solutions)

2.6131: has additional features of a FM receiver and IrDA connectivity

3.6131 NFC: includes Near Field Communication

4.6133: has a silver keypad (vs black in the 6126/6131 models), a FM receiver, and a slightly different arrangement of camera lens and external LCD screen compared to the 6126 and 6131. Only signed J2ME apps are allowed access to the network stack, with no option to change it. (released for T-Mobile)
Bugs:-

There is was a problem with the sent mailbox in the text messaging system that not opening.The system says that the operation failed.
Mms bug:-

Both the 6126 and the 6133 have been known to have some problems with the sending of MMS messages. Typically, when trying to insert a picture in the message, the screen fades out with black bars, and then to a white screen and the phone returns to main screen (called as restart). No real explanation as to why this happens has surfaced. There are various ways of fixing this problem though. Doing a full reset of the phone and not messing with the MMS settings is one. Users have been able to send messages after this, although for some, the problem arises again. Unlocking the phone is the second option. This can usually be done by shipping phone off to an unlocking website or a service center and having the service performed for a fee.