Updating iOS version on iPhone itself?

Hi, I was wondering if I updated my iPhone to the latest version, on the iPhone itself; i.e, not going through iTunes, but rather by settings>update, will I lose my photos, contacts! And will I lose my jailbreak!

You will not lose your photos and contacts, however you will lose your jailbreak. Depending on what version you're jailbreaking, you can always re-jailbreak.

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