http://isdb4l77sjqoy2qq7ipum6x3at6hyn3jmxfx4zdhc72ufbmuq4ilwkqd.onion/docs/guide/send-messages.html
To send a "live" message: Tap ⚡️ (lightning) button on the right of the message entry box. When you do it first time, you would see and alert explaining the feature. Tap "OK", and tap it again. Now you can start typing the messages, the app will be periodically sending the updates to your recipients, as you type (every few seconds, and only complete words).