Yes, you'd need to use JFBConnect for authentication. To post an action for the user, we need an authentication token, correct permissions, and lots of other stuff that we do. JomSocial's Facebook integration is good, but basic. We can't just hook into what they do and extend it for many reasons.
So, longer story short, yeah, you'll need to use us. The good news is that using JFBConnect in place of JomSocial is pretty easy. We have a
Facebook integration for JomSocial
guide and you can import any previous connections from JomSocial into JFBConnect, so your users won't have to re-connect or anything. Additionally, our automatic user creation is excellent for mobile since there's no forms to fill out to register.
Hope that helps get you started, but if you have any other questions just let us know.
Also, very glad to hear that you're using Open Graph Actions. We worked on that for many, many months to make it as easy as it is (even though it's still more complex than we like). It gives us a huge warm, fuzzy feeling hearing when people are using it
Finally, if you haven't already, please consider leaving a rating and review for JFBConnect, or our support, on the Joomla Extension Directory. It's certainly not required, but very appreciated:
extensions.joomla.org/extensions/social-...ook-integration/7215
Best of luck,
Alex