How to Send Messages to Contacts and Groups in Allo
Learn how to send messages to contacts and groups, understand delivery statuses, and what happens when your device is offline or out of range.
Every message you send in Allo travels over a local radio mesh — no mobile data or Wi-Fi required. Your phone passes the message to your Allo client device via Bluetooth, and the device then transmits it across the radio network to the recipient. Because the network is radio-based, delivery behaves differently from a typical internet chat app: messages are reliable, but the path they take depends on which devices and repeaters are reachable at that moment.
Sending a message
You can send a message to an individual contact (a private message) or to a group that your administrator has set up. The steps are the same in both cases.
Make sure your Allo device is connected
Check that your Allo client device is switched on and that the app shows an active Bluetooth connection. Without this link, messages cannot leave your phone.
Open the conversation
Tap Messages in the bottom navigation bar. Select an existing conversation, or tap the compose icon to start a new one. Choose a contact from the list for a private message, or select a group to message everyone in it at once.
Type your message
Tap the message field and type your text. Keep messages short and operational — radio networks handle brief, clear updates better than long paragraphs. Include your location or team name at the start when context matters.
Send
Tap the Send button. The app immediately hands the message to your Allo device over Bluetooth. You will see the delivery status update as the message progresses through the network.
Start every operational message with your location or team identifier, followed by status and any action required. For example: "NSP De Schakel — 12 persons present. Generator low on fuel. Requesting resupply." This format is immediately useful to the recipient even in high-pressure situations.
Delivery statuses
After you send a message, the app displays a status indicator next to it. The table below explains what each status means.
| Status | What it means |
|---|---|
| Sending | The app is passing the message to your Allo device over Bluetooth. If this status persists, check your Bluetooth connection. |
| Sent | Your Allo device has accepted the message and transmitted it to the radio network. The message is on its way, but delivery to the recipient is not yet confirmed. |
| Delivered | The recipient's Allo device received the message and sent an acknowledgement back through the network. |
| Not delivered | The message could not reach the recipient. This usually means the recipient is out of radio range, or there is no viable path through the mesh at that moment. |
For group messages, delivery works per recipient. A group message may be delivered to some members before others, depending on where each person's device is in the network. There is no single combined delivery indicator for the whole group.
Offline behaviour and queuing
If your Allo device is not connected via Bluetooth when you try to send, the app will queue the message locally on your phone. As soon as the Bluetooth connection is restored, the app automatically forwards queued messages to the device for transmission.
The queue only holds messages while the app is running. If you force-close the app before the Bluetooth connection is restored, queued messages may be lost. Always confirm your device is connected before closing the app during an incident or exercise.
When the recipient is out of range
If the recipient's Allo device cannot be reached through the radio mesh — because they are in a dead zone, their device is off, or there are no repeaters bridging the gap — the message will eventually show a Not delivered status.
In this situation:
- Check whether other messages to different contacts are delivering normally. If they are, the problem is specific to that recipient's location or device.
- Try again after a short interval. The recipient may move back into range, or a mesh path may become available as other devices come online.
- If you need the information to reach multiple people, send it to a group or a broader channel — one or more other members may be in a position to relay it.
- Contact your administrator if a device appears to be persistently unreachable.
Why does delivery sometimes take longer than expected?
Allo routes messages through the radio mesh, which means a message may pass through several intermediate devices or repeaters before reaching its destination. Delivery time depends on the distance between devices, the placement of repeaters, physical obstacles such as buildings or dense vegetation, and the current load on the network. In crisis communication, reliability matters more than speed — a message that arrives a few seconds later is far better than one that never arrives at all.
Tips for reliable messaging
- Keep messages short — aim for one or two sentences.
- Always verify your Allo device is connected before an exercise or deployment.
- Place your Allo device in an open position, not deep inside a bag or near metal surfaces.
- For information that multiple people need, use a group message instead of individual private messages.
- Ask for an explicit acknowledgement when a message is critical.