Anybody else using it?

You can download the app, then scan your Walmart receipts in on your smartphone.... overnight (or within 3 days) the app will compare the prices on your receipt to prices at local (to you) retailers, and identify any prices that were lower than you paid.

It's pretty neat, and it actually works! Your "caught savings" will be credited to a debit card.

https://savingscatcher.walmart.com/faq