Allow me here to duplicate a reply that I made in another thread dealing with the same problem. Here goes :
I found an article about IOS 9 ... :
http://www.imore.com/ios-9-review?utm_medium=slider&utm_campaign=navigation&utm_ source=imwq021ncuatm
... in which I learned that at least for NOTES, thorough synching will only occur between an IOS 9 device and a Mac running OS 10.11 El Capitan.
Here is an exerpt :
Notes is still synced using your iCloud account, so if you have an iPhone and an iPad or Mac, anything you note down on one will show up on the other or others. The new versions are different enough, however, that you can only sync iOS 9 with OS X El Capitan and vice versa. So, if you want to use Notes, you'll need to go all in on all your devices. This presents a temporary dilemma for Notes users: OS X El Capitan isn't due out until 2 weeks after iOS 9.
I wonder if our problem with purchased apps on a device not synching with iTunes doesn't simply arise from the fact that our Macs are still running Yosemite.
Has anyone tried to sync an IOS 9 device with El Capitan yet ?
YM