Will upgrading from iOS 5 to iOS 6 delete ANY data?

I want to upgrade my iPhone 4 from iOS 5 to iOS 6 DIRECTLY FROM THE iPHONE using the software update option in Settings >> General. Will doing this delete ANY contacts, emails, apps, notes and calendar reminders? I'm MOST concerned about CONTACTS. I have more than 1000 of Contacts.

It won't delete anything

I updated my iPod touch from iOS5 to iOS6.It didn't delete any of my contacts, but I don't have the iPhone. But, just to warn you… IOS6 SUCKS! I hate it with a burning passion. It adds little updates no one uses, takes away the YouTube, changes the App Store, and god forbid you try to search for an app without the App Store crashing within two seconds of you hitting search. I wish I could downgrade back to iOS5, but apparently that's impossible.

From what I have seen, it will delete contacts, game data, etc.

  • Will upgrading iPhone 4 to iOS 6 completely delete jailbreak? I know it will get rid of jailbreak, which I don't mind at all. However, I have read through different forums that sometimes the jailbreak is never completely deleted because some files still remain in phone. I would not want that to be the case (I might as well not upgrade, I don't want those files possibly causing any performance problems). So, what say you? I want to try iOS 6 on my iPhone 4.
  • Why won't iTunes transfer any song or any file to any of my devices? I have unistalled and reinstalled iTunes multiple times. When I go to to transfer a song to iphone, ipad, ipod it just freezes up and doesn't do anything. I'm running the newest version of the program. What do I need to do? Just want to fix it. Thanks. I have waited on the program to transfer just to see if it is slow or what and it took 30 mins and nothing. I can't download software updates also.
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