Tiny Umbrella is a tool that empowers users to restore the firmware in iPhone 3GS’s. The iPhone is equipped with a specific bootrom that examines the firmware which iTunes employ to restore to the device. The bootrom requires iTunes to change the images placed inside the IPSW file and add a particular signature to each image in the IPSW which is exclusively attainable from Apple.
In case users attempt to restore a firmware the Apple does not sign, the error will pop up from iTunes and they will not be allowed to restore the firmware version their device. In such a case, Tiny Umbrella proves to be extremely helpful.
Tiny Umbrella deals with the SHSH files but if one has saved them earlier. Moreover, it does not need a Jailbroken iPhone in order to restore the firmware. It is not important what firmware is installed on the device because the utility is able to get the recently signed one by default.
The only thing that reduces Tiny Umbrella appeal is the fact that it has complicated settings. But the developer provides help on the its website to ease the task a little bit.
To sum it up, Tiny Umbrella is a tiny tool with powerful capabilities.