Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
Duolingo - Duolingo is a free language learning app for iOS, Windows and Android devices. The app makes learning a new language fun by breaking learning into small lessons where you can earn points and move up through the levels. Read more about Duolingo.
Asana - Asana project management is an effort to re-imagine how we work together, through modern productivity software. Fast and versatile, Asana helps individuals and groups get more done.
Eduflow - Digital learning that actually teaches students something
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Kialo - Kialo is the platform for rational debate. Empowering reason through friendly and open discussions.