Clipping of アプリケーション (apurikēshon, “application”); an app

役に立つ: be useful, help

not ... at all

even if ...,...cannot

very, exceedingly, awfully / (before a negative form) not at all, at all, by no means

to study / to discount, to reduce the price of something

studying, studies, study

Alternative form of 勉強

the Japanese language

useless, deadhead, good-for-nothing, a piece of shit / (politics) lame duck