How does TalkJS determine whether to send an sms/email notification to a user?

TalkJS includes a carefully tuned heuristic to ensure that people who miss messages are notified quickly, without feeling like they're getting spammed.

When a person is actively looking at a specific chat, no email/sms notification will get sent. And when a person is not looking at a specific chat, TalkJS waits until the last person has stopped typing for a number of seconds, and then sends a notification to all users that missed them. This notification will group all the written messages in a single email so that your user's mailbox does not explode.