Lip-synching goes viral: the rise of Dubsmash
A smartphone app allowing users to lip-synch over their favourite songs, speeches or film quotes and share the results online has become a massive internet hit.
The "Dubsmash" app has been downloaded more than 10 million times since its launch in October, but could copyright issues cause problems for the app's young German creators?
Reporter: Ravin Sampat
Video journalist: Greg Brosnan
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