Insider Secret: download the Superstar Rewards app. Every time you use it to check in at a Carl’s Jr. or Hardee’s location you’ll earn 100 points. You don’t have to purchase to check in, your phone just has to see that you’re at a Carl’s Jr or Hardee’s location based on the GPS location. You can get a free six dollar burger with every 1,000 points that you earn, and the app allows you to check in twice daily(every 12 hours)