I now always put a handler in Starter.Application_Error. As I rarely use Debug mode it will catch and report errors that otherwise just close the app with no indicaton of what went wrong and as a bonus the app keeps running so you can do it all over again
B4X:
'Return true to allow the OS default exceptions handler to handle the uncaught exception.
Sub Application_Error (Error As Exception, StackTrace As String) As Boolean
ToastMessageShow(Error.Message, True)
LogColor("Application Error" & CRLF & Error.Message, Colors.Red)
Return False
'Return True
End Sub