"If you don't have a receipt, you really might be out of luck," said Jody Rohlena, senior editor at Consumer Reports ShopSmart magazine.
She says there are three apps they found that can help you manage all of your receipts: ReturnGuru, Lemon Wallet and Slice.
"Return Guru will let you take a picture of your receipt and then it will send a reminder to you so that you definitely get that return in before the window closes," Rohlena said.
Lemon Wallet is for anyone who doesn't want to share their personal email address for digital receipts. Lemon gives you an @lemon.com address for that. Digital receipts, along with pictures of paper ones, can be stored in the app and easily accessed for returns.
Slice gathers online receipts when you give the app access to the email you use for purchases. It also links return policies and provides customer-service numbers for participating retailers.
These apps, ReturnGuru, Lemon and Slice are free and they work on both Android and Apple devices.