If i plug my old iphone into a new itunes library what will happen?

I have my iphone, and I got a new itunes account on my new computer for other reasons. If i plug my old iphone in, will it erase all my data and text messages and photos and apps? All i want to do is download music off of my phone to the computer for other reasons also. But if i plug it in, will everything be gone?

Your contacts, settings, texts, email, apps, and camera roll photos/videos will be unchanged.

Your music, movies, and photos (that were synced from another computer) will be removed and replaced with what is in the computer's itunes library. Anything that you purchased from itunes will remain on the device and actually transfer to the computer as well (if your library has the same apple ID as your iphone).

  • Will downloading a new iTunes ruin my old iTunes library? I tried connecting my new iPhone 5 to my iTunes but it said that it wouldn't connect because my version of iTunes was really old (from 2010) and I never updated. It said I need to download a new version of iTunes (10.7 onwards) for it to be compatible with my iPhone. But my question is, IF I download a new version of iTunes, will all my old songs on my old iTunes disappear? Because if I had to re-download my whole library, I would seriously cry. That would take the rest of my life.
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  • What will happen if I plug my new iPhone into my computer? I've had an iPod for a very long time and I have all of my music currently on my iTunes. I just recently bought an iPhone and I wanted to add some tones and various music to it. Will my music be okay if I plug my iPhone into my computer?