Phacility vs Review Board: What are the differences?
Developers describe Phacility as "Phabricator, except you pay for it. Hosted tools to scale your software organization". A hosted version of Phabricator, that you pay for. On the other hand, Review Board is detailed as "Stress-free code review for teams of all sizes". Review Board is an open source, web-based code and document review tool built to help companies, open source projects, and other organizations keep their quality high and their bug count low.
Phacility and Review Board can be primarily classified as "Code Review" tools.
Review Board is an open source tool with 1.2K GitHub stars and 359 GitHub forks. Here's a link to Review Board's open source repository on GitHub.