I have emergency/bug-out bags in my vehicle, my boats, and in my house. I don't carry many tools on board, although I should, but I do carry some basic survival gear.
Ziplock bags aren't really known for keeping things dry.
They have bags called "Aloksak" that you can buy from Brigade Quartermaster. These bags are tested by the US Navy to be waterproof to over 100 feet. They're about 3 or 4 dollars for one bag, but I recommend these for storing sensitive gear like electronics.
Since being able to build a fire is very important in cold weather, especially if you're wet, I don't think a lighter or matches are adequate. That's why I recommend at least one other alternate means of being able to start a fire. A magnesium match is one method. A magnifying glass is another. Steel wool and a 9 volt battery is yet another means.
Then, there's always potassium permanganate and glycerin. Mix these 2 substances together and it causes an exothermic reaction, for starting a fire.