Make it good!
Using my iPad, I want to have good lighting, good sound and not shaky! But I don't need to spend several hundred dollars on a video camera and I don't need to edit it in a computer. Use the apps: FilMic Pro and iMovie is all it takes.
The challenge here is to compare. Is this being cheap and too amateurish? Or, does it look professional? The same rules apply whether it is a smartphone or a digital camera.
With video it is hard to keep it simple.
iOgrapher with 2X telephoto lens
RodeMic Go with ipad/iphone adaptor
Savage LED-204 light