Some items won't sync
ssome of my apps won't sync stating that they require an update but no update available
ssome of my apps won't sync stating that they require an update but no update available
Sounds like you have a 4G or later iPod. The 4 G can only go as high as 6.1.6 and many apps not require iOS 7 or later.
You may be able to install an earlier, compatible version by:
Starting when iOS 7 was released, Apple now allows downloading the last compatible version of some apps (iOS 4.2.1 and later only)
App Store: Downloading Older Versions of Apps on iOS - Apple Club
App Store: Install the latest compatible version of an app
You first have to download the non-compatible version on your computer. Then when you try to purchase the version on your iPod you will be offered a compatible version if one exists.
Some items won't sync