Using BB-8 Voice Commands
First, turn on voice commands by going to 'Settings' and tapping the button next to 'Voice Recognition' to use voice commands. At any point during play, except while on patrol and using holographic messaging, perk BB-8 up with a voice command. Say “OK BB-8” into your device to get your droid's attention, and speak any number of available commands to see how it reacts.
If your BB-8 is not responding to voice commands, first ensure you are speaking into your device held away from you at about arm's distance. Also, make sure your voice commands are spoken at a normal conversational level.
A complete list of voice commands can be found by going to the Settings section and tapping on the bubble icon next to Voice Commands.