Softros LAN messenger - LAN messenger for an internal office chat for home or business users. It does not require a server and is very easy to install and use. It supports personal chats, group chats, message brodcasting, files transfer and remote desktop access.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
MyChat - Secure instant messenger for any network
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
BORGChat - BORGChat is a LAN messaging software program.
Plivo - Plivo simplifies your customer engagement.