不常用的应用英语可以用 "infrequently used apps" 来表示。这个短语来源于英文中常用的形容词 "infrequent"，意思是"不经常发生的，不经常出现的"。
下面是一些例句：
I have a lot of infrequently used apps on my phone that I should probably delete to free up some space.
Do you ever go through your phone and delete infrequently used apps?
I only use a few of the apps on my phone regularly, the rest are infrequently used.
翻译如下：
我手机上有很多不常用的应用，应该删除一些来腾出空间。
你有没有过去整理手机，删除不常用的应用？
我手机上只有几个应用经常使用，其余的都是不常用的。
下面是一些例句：
I have a lot of infrequently used apps on my phone that I should probably delete to free up some space.
Do you ever go through your phone and delete infrequently used apps?
I only use a few of the apps on my phone regularly, the rest are infrequently used.
翻译如下：
我手机上有很多不常用的应用，应该删除一些来腾出空间。
你有没有过去整理手机，删除不常用的应用？
我手机上只有几个应用经常使用，其余的都是不常用的。