Recipes based on the content of your pantry/fridge. The ideal solution would provide a db based on sensors/user input to know what ingredients and amount of those ingredients you have. Additionally, you can hook it into some calorie counter or diet tracking/fitness apps and it will make decisions based off of that.
Then you simply specify: "I want to make dinner, what can I cook?" The app links you to the recipe and any videos for making that recipe right to your device.
I've thought of this too and there seem to be a few companies trying something like it. The difficult part seems to be keeping your stock up to date. You'd basically have to update it after every meal.
Maybe a smart refrigerator will figure it out some day or Amazon with their automated service/scanner combo. It certainly could prevent food waste.
So many people throw themselves at this space and then no one really uses their offering.
I have a loyalty card for my supermarket so they'd know almost everything I buy. If they made that data available to their users, this space might be more accessible.
No names are coming to mind right now, but I do recall several sites solving the problem of what to cook with a given set of ingredients. Tracking what you have on hand would certainly be useful.
Then you simply specify: "I want to make dinner, what can I cook?" The app links you to the recipe and any videos for making that recipe right to your device.