Purpose of custom firmware

[jleach1]

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I just read an article on redmondpie that stated were close to receiving software that will allow us to create custom firmware for ios4.1. What's the purpose? What does custom firmware do, what are the advantages, and what reasons would I have for using custom firmware instead of updating and rejailbreakiNg?

 

[Myzhi]

Few things. Custom firmware already JB the phone after restoring. It can save your current baseband. You can usually can be on latest firmware with JB much sooner than other JB methods. But, you need to have pwned JB to use custom firmware.

 

[jleach1]

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How does owning work. So it allows you to install unsigned firmware using old basebands? (new)firmware and old basebands*?