Updating a jailbroken iPhone

[crazy$hark]

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If I want to update my jailbroken iPhone 4, should I uninstall all the Cydia apps (like winterboard and appsync) and reinstall them again after jailbreaking my updated iPhone?

And if I dont will it ruin my iPhone in some way, for example slowing it down more or taking up a lot of memory?

 

[digitard]

When you update it backs up your content via sync, loads a new version of the OS, and then loads your content back.

So basically you'll lose your JB, etc, regardless and have to re-jailbreak your device. Your other data, though, will be fine.

You'll need to make sure, though, that a new jailbreak is available for the version you're updating to. Otherwise you'll need to go stock OS until they release it.