| Usage and history
- "This control box will pop you out into the open!"
- ―Luke Skywalker
Callers were designed with three basic commands: "COME" called a droid forward, "STOP" forced it to halt, and "ORDERS" caused it to enact any commands, within the droid's operating parameters, given verbally.
The Jawas of Tatooine often used callers to control their droids before selling them on. As a seven-year old child, Luke Skywalker created a makeshift droid caller in order to stargaze without his aunt and uncle's droids detecting him. It was confiscated when Owen Lars discovered him. Both Luke Skywalker and Han Solo carried callers around 0 BBY. Luke used his caller to bring C-3PO out of hiding after R2-D2 departed to find Obi-Wan Kenobi.
- Shinbone Showdown
- Star Wars Episode IV: A New Hope (novel) (First appearance)
- Star Wars: Episode IV A New Hope
- A New Hope: The Life of Luke Skywalker
- Star Wars 1
- Star Wars: Yoda Stories
- "Spare Parts"—Star Wars Adventure Journal 11
- A Guide to the Star Wars Universe
- The Star Wars Sourcebook (As "control device")
- Star Wars Campaign Pack (As "Control Device")
- Star Wars Customizable Card Game – Premiere Limited (Card: Caller)
- Cynabar's Fantastic Technology: Droids
- Star Wars: The Visual Dictionary (As "droid caller")
- A Guide to the Star Wars Universe, Third Edition
- The New Essential Guide to Weapons and Technology
- Star Wars: The Complete Visual Dictionary (As "droid caller")
- "May The Facts Be With You: Part Two: #51-100"—Star Wars Insider 95 (As "droid caller")
- The Complete Star Wars Encyclopedia
- The Clone Wars Character Encyclopedia