Currently, when the phone is disconnected the GUI is functional-looking. The box to type an SMS is disabled, and the GUI reports that no device is connected, but everything else appears as if it were working.

However, attempting to click on a known conversation in the list causes the ConversationsDbusInterface to explode, bringing down the messaging app. Scrolling up in an already-loaded conversation appears to work.

The GUI should keep doing *something* sensible when the phone is disconnected. One possible answer would be to just clear the Conversations List. It would be much cooler, though, to upgrade the ConversationsDbusInterface to not explode when the phone is disconnected, and instead just rely on its cached data.