Android MQTT Sample Application Using HiveMQ
To subscribe to a topic, click the app bar menu and select Subscribe to Topic.
To show the list of subscribed topics, click the app bar menu and select Show Subscribed Topics.
To unsubscribe from a particular topic, after showing the list of subscribed topics, click on the topic's delete icon to delete the topic.
All message types except WAITING can be deleted To delete messages, tap on the message and click delete to confirm the deletion.