Person used in musical about phone technology (4,3)
I believe the answer is:
cats paw
'person used' is the definition.
(I've seen this before)
'musical about phone technology' is the wordplay.
'musical' becomes 'cats' (I've seen this before).
'about' says the letters should be written in reverse.
'phone technology' becomes 'wap' (precursor of web browsing on mobile phones).
'wap' backwards is 'paw'.
'cats'+'paw'='CATS-PAW'
'in' is the link.
(Other definitions for cats paw that I've seen before include "Person exploited" , "part of Deuteronomy?" , "Person used by another for an unpleasant purpose" , "Dupe - nautical hitch - ripples on water in light wind" , "one being used" .)