HSHTG - Generate, manage, save and edit hashtags just in a few finger tap
ExportData.io - Export Twitter data for your business needs.
Hashtagify.me - Free hashtags search engine, with paid advanced analytics
Followerwonk - Followerwonk by Moz is a Twitter analytics tool to help companies better understand their Twitter followers.
HashtagWiki.com - Hashtag Generator Tool
Twitonomy - Twitter analytics and much more.