I've recently purchased a VBOX sport GPS to connect to my IPAD. I also use racechrono on my android phone so thought I'de try it with my phone. It doesn't pair properly to the phone and therefore the GPS data doesn't get to racechrono.
VBOX support tells me that the sport is optimised for apple products and won't work with android bluetooth but it might come as an update in the future.
I hope so because it would be great to get true 20Hz positioning.