What are some alternatives?
Bitrix24 - Bitrix24 is a free (for small businesses) social enterprise platform. It is a united work space which handles the many aspects of daily operations and tasks. Create your own social intranet in minutes!
Typora - A minimal Markdown reading & writing app.
Samepage - Easy to setup collaborative tool and file syncronization cloud application
TrackDuck - Visual feedback for web design and development.
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.
Assemblage - Powerful visual collaboration tool