I noticed that when sharing articles on social media the article images are not used - instead the site logo is used as default pic. I assume this is because there is no implementation of OG tags, at least I could not find anything related to OG tags as part of the JP-life template.
Is there a plugin you recommend or any other solution?

I dont know, if its helpful:

You can set the og-picture in the options of the menu-link:

I just saw you are using a Warp7 based theme and OG Tags are only working with Astroid based Themes like shown above

Thanks for your response!

So, would do I do then? Would installing a third-party plugin do the trick, like e.g. (like JFBConnect)?
Or is there any other way to automatically take the article images for social sharing?

Unfortunately that option is not available for the JP-life template