On: Ask HN: What do you wish someone would build?

[eterps]

An app that trains you to recognize logical fallacies and cognitive biases with suggestions on how to improve your thought process per case.

[firezemissiles → eterps]

There's the Center for Applied Rationality, as well as what the other replier replied.

rationality.org

[clementangerine → eterps]

http://www.clearerthinking.org/ is pretty close to what you're looking for.