Go to the apple inc site for the lastest OS
No. Linux cannot overwrite iPhone's firmware, as it is encrypted. Only iTunes can do that.
No
Us Jailbreak me on the iPhone 4 if you have the firmware 4.0
To check the bootrom on your iPhone: Settings General About At the Bottom - Modem Firmware
Allow it
Update the software in iTunes and it will do it for you.
You should be able to download it from http://warez.selvestr.com/?apple/firmware/iphone/ One version is not compatible with iTunes so read carefully.
Update to the Latest Firmware.
yes to the latest firmware upto date
Yes and software version
Yes.. On the iphone safari go to jailbreakme.com and it will tell u wut to do
no unless...you want to jailbreak again on the same firmwareHow to:Plug in the deviceOpen up iTunesHold Shift and then click on restoreThen browse for the ipsw (the firmware) and then restore