Gitify - GitHub Notifications on your desktop.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
GitPigeon - GitHub notifications delivered to your Mac
Zoho Desk - Industry's first context-aware Helpdesk Software
Octobox - Untangle your GitHub Notifications
Salesforce Service Cloud - Service Cloud integrates customer service with social networks and provides a self-service customer portal and knowledge base system.