Backstory: There are a bunch of items Julia and I buy regularly: toiletries, paper towels, certain food items, etc. Whenever we notice these items on sale, we purchase in bulk but often times we pay regular price. We would love to save on other (unknown) commonly bought items such as StoK cold brew coffee... I didn't realize how much I bought until I took out the recycling and there were five empty 48oz bottles.... I should lay off the caffeine.
The Idea: Have an app that's connected to your grocery stores and amazon to monitor commonly purchased items and alert you when those items are on sale.
Deep Dive: It looks like Information Machine already taps into your grocery store purchases via app api's and loyalty rewards. It also connects with a variety of other streams such as amazon: https://iamdata.co/Docs?section=user-stores-section#supportedstores. You could use this to get started quick, find all items that purchased frequently and monitor their pricing. If an item is on sale, send an alert. The app could also tell you how much and how often you buy certain items. "Purchase management" could be a monthly fee on top of the free saving program.
Validation: We would subscribe to this and I'm sure others would if it saves you money.
Monetization: You could embed affiliate links from amazon and other online retailers. You would not make anything off of in-store grocery purchases but promoting items from amazon would lead to some solid referral revenue. With amazon purchasing whole foods, I wonder if in the future you could order from amazon/whole foods online through an referral link.