Top 3 Open-Source Alternatives to Verbling

Fluent is a people-based marketing platform that uses real-time, one-to-one interaction to create custom audiences and serve personalized ads that drive performance at scale.

Mnemosyne (named for the Greek goddess of memory, Mnemosyne) is spaced repetition software...

Anki is a program which makes remembering things easy. Because it's a lot more efficient than traditional study methods, you can either greatly decrease your time spent studying, or greatly increase the amount you learn.