[gozmike]

Smooch.io (disclaimer: my company) has a really rich API for programming conversations.

You can use the API to converse with people on web chat, iOS/Android in-app chat, SMS, Facebook, Telegram, Viber, Twitter DM, WeChat, LINE+++ all through one single set of APIs. You can even send rich structured messages that are automatically translated into the best representation on each platform.

[jbuild]

Thank you so much for smooch! I would highly recommend smooch.io for anyone looking to handle conversations on multiple platforms. The implementation with Facebook Pages is brilliant.

[deet]

Agreed. Smooch is a great service.