For all using iPad, phone, camera, etc.
You need to read the instructions for your specific device. Adapters may be required. These are generally fairly inexpensive and again can be collected for long term use as they typically do no go bad and they all do pretty much the same thing.
One issue with most any phone, camera, etc.. is that the the automatic recording level, automatic gain level, or whatever they want to call it. Sometimes a limiter is in place.
All that stuff needs to be turned off and you need to learn how to operate your device in manual mode. Again that is in the manual and once in manual mode you follow the same techniques of gain structure and mic placement that one uses for any audio gear.
Does that mean you will always be able to get a great video + audio in one pass? NO. what you can do though is get great audio happening. Then after all the audio is done, go back and record a 'video performance'... or basically make a "music video" with your finished audio mix as your audio track.
In fact you probably want to record several video tracks too, and edit a final video... .the same as you do for the audio.
It's possible to record the video and audio at the same time in one pass but it's more difficult especially if your room is not good. Which most aren't.
Sound absorbing panels will drastically change the sound of your room for the better and fairly cheap. However if you have a "music room" and can place such things on the walls.... do it. Do it first.
I have a modified plan for something similar to these if anyone lives in USA, I can tell what to buy from HomeDepot and WalMart(cloth). If you put I would say 12 of these in a 300sf room there is no one that will walk in and not be able to hear the difference. It's that drastic. That would be somewhere in the $100-$150 range.
Otherwise you can get everything connected but not be able to get rid of the horrible sounding room, which in the grand scheme is the cheapest and most bang for the buck.https://www.youtube.com/watch?v=NSogByPUezc
That's the basis I modified, which covers all the wood, is easier to build, and possibly a bit less expensive.
It helps to have a nail gun and you need a saw. Otherwise it's screw and glue. I used strips of 1x1 and lattice strips.
This guy has some very nice ideas and I think I would incorporate them in to my next try. So I fell like mine make the first guy's design a little better/easier and maybe cheaper. This second guy makes them more robust and probably better. The mounting and the screen.https://www.youtube.com/watch?v=GBHYiWIJhUA
But those panels make a Yuuuge difference. More than a mic, interface, or whatever. Anyone that can't hear the difference they make probably has some very serious hearing loss. These are again, do it once and they basically never go bad. So it's money well spent.