Study carefully for each application (6)
I believe the answer is:
peruse
'study carefully' is the definition.
(I've seen this before)
'each application' is the wordplay.
'each' becomes 'per'.
'application' becomes 'use' (I've seen this in other clues).
'per'+'use'='PERUSE'
'for' is the link.
(Other definitions for peruse that I've seen before include "Look over" , "Survey" , "Browse, read casually" , "Scan carefully for rupees" , "Examine at length" .)