Involve number finally being entered in mobile code (7)
I believe the answer is:
embroil
'involve' is the definition.
(I know that embroil has the is a more specific form of the action involve)
'number finally being entered in mobile code' is the wordplay.
'finally' suggests the final letters.
'being entered in' is an insertion indicator.
'code' indicates an anagram.
The last letter of 'number' is 'r'.
'mobile' is an anagram of 'emboil'.
'r' inserted into 'emboil' is 'EMBROIL'.
(Other definitions for embroil that I've seen before include "In difficulties, involve" , "Drag in - bole rim (anag)" , "Involve or entangle in" , "Involuntarily drag in" , "Involve (someone) in a dispute" .)