iphone 6 screen cracked for no reason

My iPhone 6 screen cracked spontaneously. I was really disappointed at the quality of the phone and was shocked and angry about the service I receive with my visit to the Apple Store.

What happened was that I was in a lift with a friend, with my phone in my back pocket as usual. And all of a sudden I just heard a cracking sound, my friend thought it was my sore back cracking. But I just had a bad feeling that it was my phone. So I took my phone out, and there it was, a cracked screen for no apparent reason. I had no clue of what happened, because I didn't drop my phone or had it hit on any hard objects, it was just in my back pocket with nothing else in it.

So I made a Genius Bar reservation at the Apple Store near where I live and tried to look for similar issues that had happened to other iPhone users online. I realised I wasn't the only one that had similar problem as me. So I got to the Apple Store and talked to the staff about what happened to my phone and indicated that it was not my fault that caused the cracked screen as I did not drop it or had it hit with anything. That is why I don't think I should be responsible for the repairing cost. I told them that I never use cases for my phone, but just a plastic protective film that I got from Japan that gives protection to the back of the phone. I showed them the smooth edges and corners to prove that my phone wasn't dropped or hit anything to cause the cracks. The store manager Wilson from Castle Tower, Sydney, came and talked to me and just ****** me off so bad. He just kept saying that there was an obvious impact point on my phone indicating that the phone was dropped or hit. And I told him that it was NOT dropped and I am happy to ask for security camera footage from the lift and show him. He said "I am not saying that you dropped it, but there is an impact point, so something must have happened". We repeated on this point several times until I just got really angry and left, because he is obviously imposing that I have dropped the phone even though he is saying "I am not saying that you dropped it".

I am not making this up to excuse the repairing cost. Because with my previous iPhone 5, I have dropped my phone and resulted in a crack screen. I was happy to pay for the cost because I know I caused the damage. But this time, I just did nothing. It is just ridiculous. And the manager really needed more training on how to communicate with customers. I have been using Apple products since the 3rd iPhone. Currently I am a everything Apple person: iPad, iPhone, Macbook and TV box, and I have never had unhappy or disappointing experience with the company until now. I am definitely getting a new phone and will never return on using apple products.