[G4 General] IlyaKol:
See/try attached.

Photography is a complicated thing with many principles and techniques. I also like to say that it's half luck lol. Right place, right time type stuff (at least for the photography I did/do). In general though, the 'foundation' of knowing how to use a DSLR or in this case a smartphone with manual controls is the following:

Aperture: This is a number signified by something like F1.8 (LG G4). This signifies how wide a lens can open and maintain it's speed (by allowing more light, you can make the shutter speed fast - more on that below); the wider the better because it allows in more light. In the DSLR world, a F2.8 (fast) lens will cost 2x as much as a F4.5 (slow) lens, if not more. For the sake of the LG G4, this isn't really something you can change from what I can tell.

ISO (aka Sensitivity): ISO is one of the more important things to know, IMO. The reason is that it can have a DRASTIC effect on your images if not used properly. The way ISO works is, like aperture, a lower number is better. In the case of the G4, the ISO goes from 50 to 2700 in various increments. Say you go from 50 to 100, what this means is that your camera needs only half as much light for the same exposure because you made it more sensitive to the already existing light. When you change your ISO, you'll notice that your preview on the phone gets considerably brighter each time you go up. The reason why it is important to know how to use ISO properly (in combination with shutter speed) is because the higher you go, the more 'grainy' an image will get. This is why I always try to shoot at 250-300 ISO or below. It's a respectable range. But, the images were dark, so I had to mess with the shutter speed. Keep reading.

Shutter Speed (aka Exposure Time): This is the other vital piece of information you need to know. As I mentioned above, the lower you go in the ISO, the darker your image will be. To combat this, you need to increase the shutter (make it stay open longer) in order to allow more light in to the censor to compensate. If you shoot a picture with a 50 ISO and a 1/30th of a second shutter (reasonably fast), your image may end up being pitch black. BUT, if you shoot an image with a 50 ISO and a 2 second shutter (slow), you'll likely get something that more or less resembles an image. However, with a long shutter, which was my issue with the pictures I posted...you MUST have a tripod. The natural movement (minuscule) of the human body + wind + building shake (I was on a massive plaza with a roadway underneath) will cause the images to be blurred. If I had made the ISO 1000 and the shutter 1/60th of a second (fast), I wouldn't need to really keep steady, but the images would have been very grainy. The shutter on the LG G4 goes from 30 seconds (incredibly slow - you will DEFINITELY need a tripod unless you're dead lol to keep steady) to 1/6000th of a second (insanely fast, but you'll need a TON of ISO to make the image even remotely visible in a darker situation).

Focus: I always shoot on manual focus (even with DSLR) but you can use auto focus. This just means that the camera will try to decide what you're trying to take a picture of (objects close or far) and will focus accordingly. With manual focus, you pick if you want the camera to focus far or near.

White Balance: Honestly, this just changes the 'color' of your photos to be more warm or cool...even when I was shooting weddings I never messed with it on the camera. If I needed to change it, I changed it post-wedding during my editing sessions.

That's very basic and I hope I touched on the important things...may have forgotten a bit here or there but that should get you started in understanding the general concept of ISO and shutter speed and their relationship.