form based on the Bigtrak Jr with the 'cockpit' modified to be much smaller and streamlined. It can be controlled remotely using a computer, iOS, or Android device. The controls for the iOS / Android version allow for either tilting control or touch control. A foldable tray hides and protects the keypad from accidental input. The tray also functions as a cargo area that can detect an object placed on it. The Bigtrak XTR has two ports for optional accessories, one on the top and one on the front. The accessories are: Camera (XTRcam), computer communication module (XTRCom) that also allows another accessory to be plugged to it, light (LightBar), Infrared emitter (IRGun), and projectiles (XTRMissile). The camera can track an object. The Dubreq desktop version, Bigtrak Jr Dubreq Ltd under license from Zeon Ltd has released a 190mm long desktop version of the Bigtrak toy called "Bigtrak Jr". Like the original Bigtrak from the 1970s, it has an active accessory port for accessories including a rocket launcher (as an active accessory) and a drinks can carrier (as a passive accessory). The bigtrak sound emulator for the Apple iOS A simple iPhone app, emulates the original bigtrak sounds. Power The original Big Trak uses a 9 volt battery to power its microcontroller, while the 4 D cell batteries are used to power its electric motors. This electrical isolation helps prevent any electrical noise from the motor, speaker, and lamp from resetting or interfering with the microcontroller. The re-release Zeon version uses only 3 D cell batteries to power both its microcontroller and electric motors, while the Bigtrak Jr version only needs 3 AA batteries to power both its microcontroller and electric motors. The original optional cargo trailer uses a single D cell battery to power its electrical motor, both for driving and dumping operations, while the optional rocket launcher accessory for the Bigtrak Jr uses 3 AA batteries. Programming the Big Trak Various commands can be given, such as: "go forward 5 lengths", "pause", "turn 15 minutes right (90 Degrees)", "fire phaser", and so on. There is also a "repeat" instruction allowing simple loop to be performed, but the language is not Turing complete, lacking branching instructions; its programming also resembles the principles of turtle graphics from Logo programming language. The Big Trak also lacks any sort of sensor input other than the wheel sensors, though recent re-released versions do