I want to import images from my iphone and ipad to lightroom but only sync collections on the ipad. My iphone is "space challanged" so I do not want to sync collections to my iphone but need to sync collections to my ipad to share with clients. Is this possible or are collections sync'd with all mobile devices connected to the cloud?
No, but what really takes up space is when you enable offline editing. So enable it on the iPad, leave it disabled on the phone.