Add a small-font "last edited on <date>, last comment on <date>" to the footer, linking to the history and talk pages respectively. It is good to remind people from time to time they are reading a living document.
Topic on Extension talk:MobileFrontend
Completely agree. So much so that I've written some code to do it - https://gerrit.wikimedia.org/r/#/c/7790/
I've left out the reference the talk page date for the time being as I was worried that it would make the text in the footer too big and felt that the last edited date was much more important.
Awesome :)
It was decided this early patch required more design. We've since added a last modified date to the bottom of the article in the beta. This will soon be incorporated into the design and will probably link to the history page when we have adjusted it for mobile. Not sure when this will happen as it is not a high priority but things are moving there.