Sphero used to makeand rolling robot balls. The company's , is something completely different: a rolling rover that can connect to Arduino and Raspberry Pi, or Littlebits pieces ( earlier this year), to become a platform for a lot more.
The RVR has a color sensor (which came from Sphero's), light sensor, IR, magnetometer, accelerometer and gyroscope, and USB and a four-pin serial port where Littlebits, Arduino, Raspberry Pi and Micro:Bit hardware can plug in and become part of the RVR.
DJI's $500 camera-equipped,is a more intelligent drone out of the box, but Sphero's RVR is half the price and a lot more hacker-expandable, plus it has an already-established and pretty active Sphero EDU app to connect with. The RVR can communicate with other Sphero robots like the , possibly making for interesting robotic group-hive experiments.
I've just unboxed RVR, and it sets up and drives well. It's reasonably fast, although noisy, but the basic controls are all manual: if you want autonomous driving, you'll have to add on Littlebit kits for time-of-flight sensors and other modules. I haven't tried programming with the extras that were sent to me. I'll report back when I've tried to make some things.