my new iphone won't connect to itunes
I previously had a Samsung Android phone. I upgraded to the iPhone 6S Plus and want to connect it to iTunes. I have music and pictures on my iMac and when I plug my iPhone in, it doesn't pop up in iTunes. I have an iPhone 4 before the Android phone and have an old backup on my iTunes I would like to sync with my new phone. My new phone connects and pops up in iPhoto, so I don't know why it won't in iTunes. Can anyone help me figure out why this is happening?
iPhone 6s Plus, iOS 9.2.1