A:Answer The BB versions do not have an internal speaker rather the app/force-band makes the sounds. The R2s do have an internal speaker. All droids have patrol mode which is enabled using the app where they change direction, stop and change speed randomly. You have to keep the app open though. The droids have an impact and gyro sensors only, no visual sensor or sonar . As such, they are unable to detect/avoid obstacles. They cannot detect drop offs (stairs, table edges, etc). Since the BBs are plastic balls, they tend to slide around on a wooden, tile or marble floor. The heads on the BBs are held on by a magnet and fly off when they hit something hard enough.
All the droids can be programmed using the SPRK Lightning Lab (android, Ios), which teaches programming using different methods (one of them is a lego like visual programming language). There is also a lower level language that can be accessed using Javascript, C#, etc. You can find more info on the sphero website. If you are interested in that, it makes the droids a lot more worth while of a purchase. If you are looking for an autonomous robot with several sensors like visual,sonar, etc, these droids are not the droids you are looking for.
