Looking up to notice one’s lifted phone (8)
I believe the answer is:
admiring
'looking up to' is the definition.
('admire' can be a synonym of 'look up to')
'notice one's lifted phone' is the wordplay.
'notice' becomes 'ad' (short for advert).
'one's' becomes 'I'm' ('one is' is a formal way of saying 'I am').
'lifted' says the letters should be written in reverse (going up in down clue).
'phone' becomes 'ring' (to ring on the phone).
'im' backwards is 'mi'.
'ad'+'mi'+'ring'='ADMIRING'
(Other definitions for admiring that I've seen before include "Regarding highly" , "Looking up to" , "Approving" , "Regarding with respect or approval" , "Appreciating" .)