I really like this idea. One thing that surprised me when I entered Cognitive Behavior Therapy was the power of affirmations. The old Saturday Night Live 'Stuart Smalley' is an unfortunate social stigma that stopped me from ever taking the practice seriously until I was shown some hard evidence of it's effectiveness (no, I don't have it on hand, you can google as easily as me).

So I gave it a try. Then I tried it some more. Over time it really takes a transformation. At first I really felt like Stuart; but that is because I didn't believe the things I was saying. If I kept lowering the bar eventually I could find compliments about myself that I actually thought were true. The good feelings and confidence those smaller compliments gave me helped boost me to higher levels, and up and up, until the point now where I feel an abundance of confidence in most of my day to day interactions that I never had before.

Affirmations are really just a mind hack to architect your internal reality intentionally. You DO have an inner reality, so why not try to take control of it? :)

EDIT: Oh, but back to this startup.. I like this idea, but I hope they understand the principles behind affirmation therapy as a part of CBT. Simply telling someone they are awesome will have no actual affect if they don't believe what you are saying, so there needs to be a little bit of a day-to-day feedback process to hone in on the target emotions you want to generate. I doubt this much effort is being put in, but I might be willing to drop $10 to find out. :)