iPhone just for future reference...

[aPple nErd]

so, can a 4s actually by downgraded on iOS 5? i mean like from iOS 5.1.1 to iOS 5.0.1 for example. and can it upgrade from 5.0 to 5.1.1 for example, with blobs of course. so whats the 4s downgrade method, and how do i do it? also, may seem like a dumb question, but why can't a 4s be downgraded from iOS 6.x.x to iOS 5.x.x? thanks.


p.s. i never had a 4s, just a 4 and a 5, so on the 4 downgrading is simple, and on the 5, its of course not possible.

 

[darricksailo]

so, can a 4s actually by downgraded on iOS 5? i mean like from iOS 5.1.1 to iOS 5.0.1 for example. and can it upgrade from 5.0 to 5.1.1 for example, with blobs of course. so whats the 4s downgrade method, and how do i do it? also, may seem like a dumb question, but why can't a 4s be downgraded from iOS 6.x.x to iOS 5.x.x? thanks.


p.s. i never had a 4s, just a 4 and a 5, so on the 4 downgrading is simple, and on the 5, its of course not possible.

for iOS 5, you can only re-restore to the version you are on assuming you have SHSH blobs for them. i believe you use redsn0w for the re-restore

the reason why it's not possible for devices past iphone 4 is because the newer devices do not have a bootrom exploit

 

[BumpyFlatline]

for iOS 5, you can only re-restore to the version you are on assuming you have SHSH blobs for them. i believe you use redsn0w for the re-restore

the reason why it's not possible for devices past iphone 4 is because the newer devices do not have a bootrom exploit

You also must have upgraded to your current iOS5 version via iTunes and not OTA. If the current iOS5.x firmware was installed via OTA you can not re-restore on the 4S.

Just an FYI to the OP. Here's the link to the original blog post. OP, you should read this to make sure you have all your bases covered just to be safe. It explains everything you need to know about iOS5.x re-restores for your device. You may or may not be able to do it.

http://blog.iphone-dev.org/post/33546509336/restoration-reinvigoration