Power through USB

[Zman350x]

I have a small device w/ a USB port on it. Normally you plug it into a computer and it gets power through the USB and sends the data through it. This all works fine, however, I plan to plug it into my iPhone, which doesn't output a charge so it doesn't work. Would something like this work? plug it into the device, and put one of the split ones into the phone and another into an outlet? https://www.amazon.com/JoyReken-Compact-Splitter-Notebook-Keyboard/dp/B07QCZ7VX2/ref=sr_1_12?keywords=USB+Splitter&qid=1564008519&s=electronics&sr=1-12

I know this post is a jumbled mess and I hope it makes sense, also the answer's probably super obvious and I'm just dumb.

 

[Trotter]

Powered USB hub, maybe?

 

[S0ULphIRE]

What is the device that you're trying to plug into your iphone?

 

[Zman350x]

I have an app to use the phone as a monitor, so the device is a HDMI to USB capture card/adapter. The capture card works but is un-powered by the phone, as I said above.