I'm sure Apple is doing more than other companies to improve the conditions - but that doesn't mean the conditions aren't horrid as they are.
I don't know what Apple could change and how much more it could do. But if we look at the large picture, as long as we keep buying new phones, tablets, and computers on a couple yearly basis at affordable prices, there will be people out there who will build them.
Gone are the days when German craftsmen hand-polish your Leica camera that you pay a fortune for. Then you had a camera that lasted a lifetime or longer, you respected it, it worked perfectly, and the people who built it didn't have to hurry, they had time to sleep and they did something that required high skill and they were respected for that. You can pay a fortune for something you know you need, and you know you'll only have to buy it once in your life. If you buy an iPhone, you won't want to pay a fortune for it because no matter how cool it is now, it will be useless in 3 years.
The way to improve working conditions would be to be okay to pay far more for these products, and to stop upgrading them every two years by simply throwing them out and buying new ones just because the latest software update made the old one slow as hell.
Also, why do we need more tin for these products? Surely the amount of tin being used at any one time is constant, except we aren't recycling the products correctly.
You can't blame Apple for this. The entire Western world is responsible for creating and maintaining consumerism. We are the ones that generate the need for such products. There are more and more people in the world, more of them want to own more products. Now people have at least one computer, and many cell phones, as well as tablets and other gadgets. Someone has to build these. If Apple didn't comply to these needs, some other company would. The point is, we want stuff, they build stuff. We want it cheap, they work cheap.