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.
SaaSPlace - Acquire, invest & sell SaaS products, plugins and apps
KanbanMail - A Kanban board for your emails.
pickSaaS - Hundreds of SaaS products, analyzed.
Sunsama - Calendar and scheduling for teams
Productool - As Product People, we hunt for new SaaS products every day, and they play a major role in making our lives easier — that's why we curated a list of the top 100 SaaS products that millions of users love.