It's a tool that lets you browse the Nokia Care (or whatever it's called) servers and see what firmwares are available.
Symbian Toys - Software NaviFirm+ to dowload the firmware of your Symbian smartphone
Just wanted to add this disclaimer to those who were asking what Navifirm is;
this tool is only for advanced users / users who know what they are doing and are aware of the risks.
If you flash the
incorrect rom
you will destroy the phones cellular radio (and probably more than that), as there are many variant models of a phone (designated with a specific number in the form of
RM-XXXX) sold in specific regions thus the firmware only has support for the bands used those regions.
As a rule of thumb, you should flash the Country Variant (CV) ROM which supports your phone - this will also debrand your phone - [Meaning No Carrier splash screen]. The easiest way to check is by going to Microsoft.com, search for your phone and chances are your region will be shown at the bottom of the website Or alternatively you can check the about section on your phone.
However it will also mean, once the update rolls out for the
Country of the ROM you flashed only then you will get the update and
NOT when your carrier releases it (the sim you're using or the ROM the phone was previously running before the flash).
Furthermore ROM flashing
does not sim unlock your phone.
So best double check you are flashing the correct firmware for your specific phone and use the USB cable supplied with the phone as that is factory cable.