https://www.theverge.com/2018/2/21/17036126/google-smart-reply-app-slack-facebook-messenger-whatsapp-hangouts-hands-on

Last week, Google’s Area 120 division announced that it’s building a new app that would add Smart Reply features to a number of popular messaging apps, such as Facebook Messenger, Slack, and Hangouts. This week, Android Police surfaced an APK so you can download and try Reply on Android devices right now. Note, however, that it’s just a beta, so try it at your own risk.

In my initial testing, the app does work as promised, though it is a little less contextual than Gmail’s version of the feature. When you set up the app, you can add different modes such as “Vacation responder” or “Urgent sound” so the app can detect tones from incoming messages and know how to respond to them. Based on your phone accelerometer, Reply can also tell if you’re in a vehicle or biking and can auto-respond appropriately. One of the options in Reply is “sleeping,” though it is unclear to me how the app can tell when you’re in bed versus just hanging out in your house with your phone on a table.