LinkChecker - LinkChecker is a free, GPL licensed website validator.

Mustr - Mustr is a public relations platform that helps the media team in organizing the network of journalists and bloggers and maintaining relations with them.

Xenu's Link Sleuth - Xenus Link Sleuth checks Web sites for broken links.

Crowdly - Crowdly is a social advocate management platform, helps brands find, rank and engage their top advocates on Facebook.

Integrity - Feature comparison of link checkers for Mac: Integrity, Integrity Plus and Scrutiny

Jamballa - Jamballa is a platform that enables brands to reach bloggers and influencers more easily to promote their products and services, and to reach the targeted audience.