EZ Texting - EZ Texting provides SMS marketing solutions to businesses of all sizes.
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
Textmagic - The all-in-one solution for all your business texting needs - marketing campaigns, two-way SMS chats, reminders, notifications, and internal staff communication.
tawk.to - tawk.to is a free live chat app that lets you monitor and chat with visitors on your website or from a free customizable page
SimpleTexting - SimpleTexting offers SMS and text marketing services for companies of all sizes.
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.