I run a robotics club where I teach. A group made an RC car arduino-Bluetooth-android. It's done but they keep getting "socket Failure" or failed on their phone. The Bluetooth is HC-06. We have tried everything we could think of. Any help would be great!
I did a quick Google and the Internet generated numerous hits.
HC-06 android socket failure
There are too many issues to speculate, but try connecting to a Bluetooth PC and use a terminal program to validate the BT module is working correctly.
Ray