What are some alternatives?
When comparing Iris and Atina, you can also consider the following products
Moka - Moka is a Gnome Shell theme that uses simple geometry & basic colouring.
Flow - Stop managing projects from your inbox.
Materia - Materia is a development environment to build advanced mobile and web applications.
Nifty Project Management - Manage projects, work, and communications in one place.
Eyeleo - EyeLeo is a handy PC application that reminds you to take a break for your eyes.
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.