The two key questions of introspection are:
What do I feel?
Why do I feel it?
~ Ayn Rand
When you feel a strong (probably disturbing) emotion, open the app on your smartphone and answer these two questions presented to you. The app will store the time and your answers so you can always look back to learn more about yourself.
You might want to have less.
An app where you set up what is the maximum number of items you want to have in your life. Then you list all the items you currently have. If there are more than what you deem as the right number, then you have to get rid of the extra ones. From that point on, any new item has to push out another one.
Wouldn’t it be interesting if we could look at other people’s notes and what they highlighted while reading a certain book?
Allow people to add their own notes to listed books (and add new books if they are not yet listed), and keep them in a central repository online. Everything should be indexed and searchable.
Firstly see how your interests are connected to each other and how they relate to the vast interest cloud that exists on the world wide web. Secondly, get hints as to what other subject matter are closely related to your interests.
Map the world wide web based on subjects. See clusters of information out there and how they are connected. Than see your own interest map emphasized on the whole map. This will also show you other interests that are bordering your map of interests.
Being exposed to people talking in the language you want to learn helps you embed the language.
Have a central listing of online radio stations categorized by language, region, and level of language used (for beginners, more advanced etc.)