Voice recognition and control system specialist Nuance has released an update for its_Dragon Mobile Assistant app for Android_that introduces voice unlocking of a handset for the first time, as well as a couple of other minor updates. To use the new voice unlock feature, you just need to teach the app your voice by saying 'Hello, Dragon' three times and it then locks on to your own personal voice print. From here on out, the phone will only respond to your voice. Once taught, every time you say "Hello, Dragon", it will open the app ready for further voice commands...