勝かっ手てアプリ

noun

unofficial app; app installed without carrier approval

Dated term from the feature phone era, referring to apps installed without the carrier's permission, often via sideloading. Compare 野良アプリ, which is a more common modern term for unofficial apps.

See also: 野良アプリ

• 昔むかしのガラケーでは、勝かっ手てアプリを入いれると保ほ証しょうが無む効こうになることがあった。

  On old feature phones, installing unofficial apps could sometimes void the warranty.

• 勝かっ手てアプリはキャリアの審しん査さを通とおっていないので、動どう作さが不ふ安あん定ていな場ば合あいもあった。

  Since unofficial apps didn't pass carrier review, they could be unstable.