Macs and iPhone/iPads - and photos
I dunno about Capture One Pro 6, but the latest version (and Express) have a feature that starts a server on your Mac (basically a web server) and has an app called Capture One Pilot that can access the images. You can do certain things to the images but right now I can't recall the whole range of options.
There's also Photosmith, but you need Lightroom. It's great, better than Lightroom Mobile IMHO because it allows you to do more.
Alternatively, you can use iTunes to sync photos back and forth. Kinda clumsy, and really not great if you deal with RAW photos, although there are more apps now on the iPad that can make sense of RAW files and create a workflow that is efficient (Photogene4 maybe).
And for metadata, check out PhotosInfoPro.
And no, don't expect flawless. Synching is rather problematic if you are expecting something like contact or calendar sync. But if you go simple, move files on, edit, move files back, for instance, it can work fine.