What are some alternatives?
When comparing ProProfs Knowledgebase and Airim, you can also consider the following products
ZenDesk - Zendesk is a beautiful, lightweight help-desk solution.
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!
Manula - Manula is an online software for creating user manuals.
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
Helppier - Helppier provides tools to create interactive user guides in minutes.