They have the right to prevent people from copying their products. But not opening their products. Period.
It's not their phone.
What "rules" do you imagine apply in this case? I *own* the phone. I can do whatever I want with it, including destroy it. There are no rules preventing that.
Once you move out of your parents house and are able to afford your own things, you will learn that you generally have the right to do with them as you please. Of course, you will also be responsible if you break something you own. But that's also part of being a grown up.
You can deal with your phone however you want. And I can deal with mine however I want. I don't understand why you want to interfere with my use of my property. Or even why you care.
Do you believe in Santa Claus, too?
You.Hate.Freedom.
This is idiotic. I bought my phone; I'm not renting it. Once people have sold things to you, they are *yours*. I have the right to fix them, or break them, as my heart desires. Seriously, what kind of country do you think we live in?
Umm, the terms and conditions don't prevent opening up the phone.