I have an 4th gen ipod touch and a Ipad 3 which I JB'ed up to IOS5.1.1 when it was the in thing, I have been lazy and since until recently few apps have demanded anything higher, I have just left it as is.

I believe the highest I can go is 6.12 and I found a few guides on updating but they all seem to be outdated and any I tried to follow using my ipod as a test failed, this may or may not be because I have no idea what I am doing though.

Whats the shimmy on this, I keep hearing people talk of SHH blobs and I either needed to have back them up in the past or I should do now, but to be honest they could be talking in code about thier favorite sexual fetish for all I know.