我猜你是想说“在手机上唱歌”，对吗？如果是的话，那么我们可以用“singing on a mobile phone”来表达这个意思。这个短语的来源可能是人们平常会在手机上使用音乐播放器，或者是通过手机上的唱歌应用来进行唱歌。下面是一些例句：
I love singing on my mobile phone. It's so convenient and fun!
He's always singing on his mobile phone. I think he's addicted to karaoke apps.
Have you ever tried singing on a mobile phone? It's a great way to pass the time.
She's really good at singing on her mobile phone. She always gets perfect scores in the karaoke app.
I used to sing on my mobile phone all the time, but now I prefer to just psten to music.