Technically, the goal of this service (whether the owners describe it this way or not) is to find the unit elastic point on a product's demand curve. In theory,

Technically, the goal of this service (whether the owners describe it this way or not) is to find the unit elastic point on a product's demand curve. In theory, assuming a linear demand function, profits are maximized at the price and quantity associated with the point where price elasticity of demand = 1 (or equally, where marginal revenue = 0). If your current price is higher than the unit elastic price, your total revenue increases by lowering your price. If your current price is lower than the unit elastic price, your total revenue increases by raising your price. These topics are covered in any intro to microeconomics course (as well as any MBA economics course). That being said, I like the idea, and I wish you guys luck. I'm actually building something similar (YC application in the pipeline) but with a more specific focus on a particular set of markets.