Zendesk - Zendesk is a beautiful, lightweight help-desk solution.
SE Ranking - All-in-One cloud-based SEO software for agencies, marketing teams and webmasters
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
DeskAlerts - Send alerts to any corporate device: PCs, phones, tablets, etc.
HelpScout - Help Scout is a simple, straightforward way to provide excellent support
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.