Some apps let you get coupons by taking a picture of your receipt with your phone. Here are four that I use. These apps may be USA only.
Coupons.com
This is the one I like the least. You have to choose the coupons you want before you scan your receipt. I don't always have time to scan through all items. There are a list of about 100 stores but if you do not see your store, then you can upload it as an unlisted store. Generally the stores are physical locations but I do see the online Shipt and Instacart services as options. I still think you need to scan a physical receipt though. Some stores like Giant let you link their loyalty card to make the process automatic.
Paypal is currently the only option to receive your cash back. I don't think there is a minimum amount that you need but it can take a week.
Ibotta
My number 3 choice. It is similar to Coupons because you have to select the coupons before you use them. But it often has generic options, such as $0.50 to submit any receipt or $0.50 off any type of eggs. So even if I don't have time to scan through all possible coupons, I can still get some cash back. You can also connect it to your online stores, such as Target and Walmart, for automatic cash back. Besides coupons, it has a browser extension that helps you get general cash back for shopping, including certain Amazon products.
You need a minimum of $20 before you can withdraw to your bank, paypal, or a gift card. It has a referral program where the referrer can get $10 but unfortunately I don't see a bonus for the invitee. Referral_Link Non-referral_Link
Fetch Rewards
I like this one because I can scan a receipt (well take a photo of it) with my phone and it will automatically find coupons that I am eligible for. Even if there are no coupons for me, it will still give me a few points just for trying. You can connect your Amazon account and your email account for eReceipts. There is a button to check your eReceipts. I'm not sure if it is completely automatic or if you have to click that button, but I usually click it to be safe.
You can redeem your points for gift cards. The minimum amount appears to be $3 but it is more efficient to go for the larger amounts. There is a referral bonus where we both get 2000 points ($2) - https://fetchrewards.onelink.me/vvv3/referraltext?code=GV7D5
Swagbucks
Swagbucks is many things but it does have a way to scan receipts and get general cash back. You have to select the coupons you want before scanning your receipt. However, the list is smaller than Coupons/Ibotta and it does have generic categories. You still get a few points even if no coupons were found.
You redeem your points for gift cards with the minimum at $1. Again, it is more efficient to go for larger amounts. The referral program can give the invitee a bonus 300 points ($3). There are a few extra points for installing the browser extension. The referrer gets a bonus 10% of some of the invitee's points. https://www.swagbucks.com/lp-savings-button?cmp=695&cxid=swagbuttonref&rb=58568506&extRefCmp=1&extRb=58568506
These coupon apps are more efficient than crypto faucets. My wife and I fight to see who can scan the receipt first. She usually wins. It is not as efficient for both of us to have these apps but we have fun.
Please post your tips (about coupon apps) and referrals for other coupon apps that I need to try. Check out other referral bonuses here - https://invitation.codes/@j_wowza