My mobile phone is extremely useful.

我的手机极为有用。

《柯林斯英汉双解大词典》

My mobile phone is helpful.

我的手机很有用。

youdao

Why not use my mobile phone?

为什么不用我的手机呢？

youdao

If it can display information off my mobile phone, too, all the better.

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"With Instagram for Android I can upload photos of abandoned beers on the backs of bar toilets RIGHT from my mobile phone!"

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What goes on there is obviously top secret, for cameras were confiscated upon entry and my mobile phone received a sticker over the lens.

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