A Vox-drone is a mobile communications platform used commonly with the Imperium of Man to carry recorded messages. The Vox-drone is an oblate metal unit about the size of a citrus fruit that has an anti-gravity emitter built within it.
The Vox-drone carries messages to people it is programmed to find by using a recorded pheromonal trace to track down the person for whom its message is intended. The drone can record short audio and holographic messages that will only be played for the person whose pheromonal markers match the drone's data set.
Because it carries a relatively small power cell, the Vox-drone can only be used for short-range communications and is generally used within the spires of wealthy hive cities to carry personal or business-oriented messages between the members of the hive's nobility.
- Warhammer 40,000 Wargear (4th Edition)