The average American household throws away about one-quarter of the food it buys each year - a needless waste of money and valuable resources and a drain on the environment. Rachel Cohen designed a mobile app that helps users waste less food by addressing three common pitfalls: keeping track of what's in the fridge and pantry so people don't buy more food than they need, reminding people that their food is about to expire so they'll use it before it goes bad, and educating them on whether food is safe to eat so they don't mistakenly throw out anything that's still good.