I've installed the SmartTalk app on two android phones, each using a unique BT ID. Installation and registration went without a hitch. On one phone I am able to successfully make calls, but on the other it fails.
When I attempt to make a call from my phonebook , it gets as far as dialling the number, and the destination phone rings, But then I get a message on the android phone saying "Unfortunately, BT SmartTalk has stopped." at which point the destination phone continues to ring.
Similarly, if I attempt to dial a number from the numeric keypad, I get the "Unfortunately, BT SmartTalk has stopped." message as soon as I press any number key.
One further point which may or may not be relevant. I did have the app working successfully on this particular phone around 18 months ago. Perhaps there has been a subsequent update which has broken the app? Maybe installing an earlier version (if I can find one) would do the trick?