Textmagic - The all-in-one solution for all your business texting needs - marketing campaigns, two-way SMS chats, reminders, notifications, and internal staff communication.
TapTalk.io - TapTalk.io is a complete in-app chat SDK and messaging API - Easy integration and customizeable.
SimpleTexting - SimpleTexting offers SMS and text marketing services for companies of all sizes.
Lets Chat - Open source self-hosted chat app for small teams
Mobiniti - Mobiniti offers a mobile marketing platform for clients to invite customers to engage with their brand through SMS via their mobile phone.
WeChat API - WeChat API and SDK allow developers to access and integrate the functionality of WeChat with other applications.