How big should a phone be?
24 February 2013 Last updated at 02:12 GMT
Thousands of mobile phone experts are descending on Barcelona for the annual Mobile World Congress, the mobile industry's main showcase event.
One of the big questions being discussed this year is how big do consumers actually want their smartphones to be?
Designers are even talking about a grey area between the design of the phone and the tablet, known as the 'phablet'.
BBC News went to a UK Trade & Investment event in central London, a warm-up for firms to test their ideas before they go to Barcelona.
Delegates were asked: "What size do people actually want their smartphones to be?".
Video Journalist: Dougal Shaw