engageSPARK - engageSPARK offers telephony and messaging engagement solutions.
Dialog Messenger - handy and feature-rich enterprise multi-device messenger available for server or cloud – Slack-like, but not Slack-limited
ClickSend - ClickSend builds communication software and tools for businesses. We offer SMS, MMS, Voice, Email, Online Mail and even Fax. All accessed via our Dashboard, app, flexible API or integrations.
Ripcord - A desktop chat client for Discord and Slack
Screen Magic - Screen Magic is a business texting application for CRM's like Zoho, Salesforce and Oracle.
Ziggs - Smoothly Share Content Between Devices!