What are some alternatives?
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
ZenDesk - Zendesk is a beautiful, lightweight help-desk solution.
Zoho Desk - Industry's first context-aware Helpdesk Software
HelpScout - Help Scout is a simple, straightforward way to provide excellent support
Front App - multi-channel inbox service for collaborative teams
Bitrix24 - Bitrix24 is a free (for small businesses) social enterprise platform. It is a united work space which handles the many aspects of daily operations and tasks. Create your own social intranet in minutes!