女友達のスマホに入ってるアプリが男子高校生すぎるという話題から「お前のラインナップは無趣味の虚ろなOL」と言われてウケた。
I especially don't understand why is there a から after 話題. But also, what does ラインナップ mean there? Does it refer to the apps that the person has got on their phone?
I'd translate that as:
during a talk about how, judging by the apps in my female friend's smartphone, I would say she's a high school boy, I was told that my apps are those of a boring office lady
But that doesn't sound right.
This から is "from (such-and-such a 話題)" or "after (such-and-such a 話題)". This 話題 is modified by everything from 女友達 to という. And ラインナップ refers to the apps of the writer's own smartphone (you can tell this because of the passive voice 言われ). 男子高校生すぎる is a loose way of saying "too much like a male high school student".
女友達のスマホに入ってるアプリが男子高校生すぎる
The apps in the smartphone of a female friend of mine are too "male-high-schooler-ish" (i.e., too much like those of a typical male high school student; perhaps she had a shonen-manga reader or a bishojo-game)という話題から
... from such a topic, (the conversation evolved to the following ...)「お前のラインナップは無趣味の虚ろなOL」と言われ
I was told (i.e., argued back) that "your line-up (of smartphone apps) is (like that of) a hobby-less empty female office worker",てウケた。
...and it cracked me up.
You are confused about who said what. The author said to the 女友達, "Your apps are like those of a 男子高校生!". Then the author was argued back by the 女友達, "But yours are like those of an empty OL!". Which made the author laugh.
