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Android

Messaging

Starting a Private Message

To send a message to another member:

  1. Tap the floating action button (new message icon) in the conversation list.
  2. Select a member from your organisation’s approved member list.
  3. The conversation opens. Type your message in the input field at the bottom of the screen.
  4. Tap the send button to deliver the message.

Your message is encrypted on your device before it leaves. The recipient receives the message encrypted and decrypts it on their device.

Group Messages

Group threads appear in your conversation list. To send a message to a group:

  1. Tap the group conversation to open it.
  2. Type your message in the input field at the bottom.
  3. Tap the send button.

All members of the group receive the message. Each message is encrypted with a key shared among group members.

File Sharing

To attach and send a file:

  1. Tap the attachment icon in the message input area.
  2. Select a file from your device. Files up to 10 MB are supported.
  3. The file is encrypted on your device before upload.
  4. Complete the send action to deliver the file.

Broadcasts

Broadcasts appear in your conversation list, marked as broadcasts. Broadcasts are read-only — administrators send messages to all members, and you can read but not reply. If you need to respond to a broadcast, contact your administrator.

For the portal workflow that sends broadcasts, see Broadcast. For the delivery model behind them, see Broadcast Messages.

What the Server Can See

The server receives only encrypted messages. Your message content, file attachments, and metadata are encrypted on your device using the Signal Protocol. The server cannot decrypt or read your conversations.

Battery Optimisation and Push Notifications

Android’s battery optimisation can delay push notifications. If you notice that messages are not arriving promptly, check your battery settings:

  1. Open Settings > Battery (or Device care on some devices).
  2. Tap Battery optimization or App battery management.
  3. Search for SemaFore and set it to Unrestricted.

This ensures push notifications wake the app immediately when messages arrive.

Message Storage

Messages are stored on your device only. If you uninstall the app or register a new device, your message history on the previous device is not recoverable.