The AT&T iOS SDK is a development kit for multiple AT&T APIs i.e. Speech, Advertising, and In-App Messaging, written in Objective-C. This SDK provides developers a way to integrate these APIs with their mobile applications using Objective-C.
Twilio has announced the Twilio API for WhatsApp which allows developers to integrate with applications nearly every messaging channel via one Twilio Messaging API. Among the messaging channels the API supports are SMS, MMS, Facebook Messenger, RCS, LINE and the newly added API for WhatsApp.
Facebook has announced the launch of beta access to a new Messenger API feature which will provide support for Instagram messaging capabilities. Facebook is hoping to provide businesses with the tools necessary to improve customer satisfaction and facilitate meaningful conversations on Instagram.