Chick-fil-A giving away free chicken nuggets until the end of September, but there's a catch

Chick-fil-A is giving away free chicken nuggets!

All customers who order via the Chick-fil-A One mobile app can score a free eight-piece order of chicken nuggets. Each person with the app can redeem the offer once and the offer is only valid until Sept. 29.

The chicken chain says joining the Chick-fil-A One program comes with a lot of perks. The app is a reward system for loyal customers.