Thoughts from a reflective educator.
Imagine you put your food into a re-usable container, but before putting it into your refrigerator, you scan it first, and when prompted, tell your refrigerator what it is (either verbally, or using text). Your refrigerator (or a small computer attached to the outside of it for "analog" refrigerators) records what you've entered into it, and the date and time you entered it. Every time you remove something from your refrigerator, you scan it on the way out, so that the refrigerator always has a record of what is inside it, and when it was placed inside it.
You could then ask your refrigerator (using voice-recognition software) what would be good to eat, and your refrigerator could also remind you that your food needs to be eaten soon. Further, if you also scanned in raw ingredients (and maybe did the same for dry goods stored in your cupboards/pantry), your refrigerator could recommend recipes. Your smartphone could have an app which was aware of the data from your refrigerator, and could act as a shopping list. Or, instead of an additional device on the refridgerator, each person who used the fridge could have the app on their phone.
I wonder how long it would take such a system to save you enough money from not wasting food so that it would be affordable?