You are correct; we don’t post-process the entry to either convert it into an existing tag or create a new tag. This is a known limitation and is not currently slated for the first release of our new Jive Mobile app. We do of course recognize its value though and will weigh it against other priorities for future updates.
As always, getting others to vote on your ideas will help us with that prioritization process. ☺
Thanks for the feedback!