Smartphone software wasn’t accurate or practical (7)
I believe the answer is:
applied
'practical' is the definition.
(similar in meaning)
'smartphone software wasn't accurate' is the wordplay.
'smartphone software' becomes 'app' (short for application).
'wasn't accurate' becomes 'lied' (told a lie).
'app'+'lied'='APPLIED'
'or' acts as a link.
(Other definitions for applied that I've seen before include "having a practical character" , "Put into practice or requested" , "Assigned < practical" , "Useful" , "Went for university place" .)