What are some alternatives?
ZenHub - ZenHub is how the world's best software teams work together. Trusted by NASA, Docker, and Rackspace. Start free today!
Intercom on Product Management - The ultimate resource for aspiring product managers
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.
productboard - Beautiful and powerful product management.
Flow - Stop managing projects from your inbox.
Instabug for Product Managers - Collect and understand user feedback