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Convenient; handy; useful
このアプリはとても便利です
This app is very convenient
便利な場所に住んでいます
I live in a convenient location
Often used to describe things that make life easier or save time
便利 is often used to describe things that save time or effort, such as convenient stores (コンビニ) or useful apps.
When used as an adjective, it takes the form '便利な' before a noun.
From the Chinese characters '便' (convenient) and '利' (benefit)
Can be used as a na-adjective (便利な) or as a standalone adjective (便利です)