Why and for what purpose would you want to do this. Seems many other ways/products to obtain external power easier and reliably.
I have seen videos of a few phones powering USB hard drives without the need for a separate power supply to power the drive. I just wondered if anyone knew of any phones that could potentially power 2 USB hard drives at the same time without a separate power supply? I want to do this to backup / sync drives without a computer while travelling. Granted, this will be a major drain on the phones battery, however I just want to know if it is possible?
With the advent of USB C and power delivery, I think there are more opportunities. I have even seen a video of someone charging a laptop with a phone over USB C (for a few minutes)
Does anyone know of any phones that could potentially power 2 USB hard drives at the same time without a separate power supply?

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