This is the 18938th most frequent Korean word.
써보지
"써보지" means "try using" in English.
The verb '써보지' (haven't tried using) is derived from '쓰다' (to use/to write), with '-어 보다' added to indicate trying something. The '-지 않았지만' denotes negation, meaning the action has not been performed yet.
이 펜을 써보지 않았지만 정말 좋아 보이네요.
I haven't tried using this pen, but it looks really nice.
The phrase '써보지 않고' indicates abstaining from trying or utilizing something ('new app' in this case), using the conjunction '-고' to link actions.
새로운 앱을 써보지 않고 기존 것만 사용해요.
I don't try the new app and only use the current one.
Here, '써보지' represents the subjective action of trying ('연필', the pencil), forming part of a past completed action shown in the entire sentence.