Zendesk - Zendesk is a beautiful, lightweight help-desk solution.

Aboardly - IFTTT for automated customer emailing

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

BurnChurn - 🔥 Reduce churn and track exit feedback for your SaaS

HelpScout - Help Scout is a simple, straightforward way to provide excellent support

Customer.io - We make it easy to send emails triggered by user behavior. Build, measure and improve your emails to activate and retain users