The BlackBerry 10's TimeShift and BlackBerry Balance features

The first two handsets powered by the new Blackberry 10 operating system have been unveiled, at a launch event in central London.

The Z10 is controlled via a 4.2in (10.7cm) touchscreen while the Q10 has a smaller 3.1in (7.9cm) screen and physical keyboard.

The UK will be the first to get the Z10, when it launches on Thursday.

Its appeal could determine whether the firm - which has switched its name from Research In Motion to Blackberry - has a long term future.

The BBC's Mark Gregory tried out the Z10 with Blackberry's product manager Nick Webb.