For sub-hour scheduled or recurring tasks, most users prefer a scheduled background task with DJ, rather than old-school cron. There are a bunch of ways to do this, for example:
Great! I posted that hoping that there would be a solution. I've looked around delauyed job trying to find some scheduling funciton but I didn't look close enough it seems. Thanx!
You could have a cheapo server be the "timekeeper" that sends a web request every minute to a heroku app which in turn does whatever you need.