What are 3 mobile apps you wish existed but don't?

1. A real time, whole health tracking app

Smart watches will soon likely be able to do this, but I'd like an app that shows real time vitals including blood pressure and blood glucose levels. It could tell you which types of foods and situations to avoid to protect your health.

2. Codebase tour guide

An app where maintainers and creators of popular open source projects would give "guided tours" of their codebases, pointing out specific problems they encountered and solved and explaining the reasons for their decisions.

3. Knowledge assistant

An app that somehow assesses your knowledge or skill level in a given field and points you to resources to help you reach the next level in proficiency