phone tablet laptop or desktop

Yes.

Are you talking about any particular situation? What we use most often? I don't use my desktop to make phone calls (though do sometimes use my laptop with Microsoft's "Your Phone") and I don't use a phone as a file server.

I use a desktop only. I do not like laptops because most of the time their battery life sucks bad. I do not use my phone except for FB and calls due to the same reason.

All of the above.

I have a tablet which I mostly use and a pc.

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