I have recently encountered a problem with my iPhone 4S. The lock button became sticky for a couple of days before it stopped working entirely.
I visited the genius bar at the apple store Braehead where the "Genius" was very professional and I couldn't fault this service. However, he was unable to repair my phone as it was out of warranty and would be chargeable.
I believe that this is a common fault with the iPhone 4 and 4S and after a quick internet search found a thread on your site relating to this which had 854476 Views. I understand that phones can develop issues but within 18 months and out of the blue. I felt let down by the usual high standards I usual expect of apple.
To make things worse, whilst in the Braehead store, a woman had the same issue as me. Whilst my assistant was in the back checking my phone, another genius served the woman, and i couldn't help but overhear that her phone was also out of warranty. The assistant explained the problem to the woman and said that she would need a replacement phone and asked if her phone was backed up. When she confirmed it was, the assistant began to replace her phone and the woman asked is there a charge for the new phone, to which the assistant replied "not unless you want there to be."
I was outraged that there was one rule for one customer and one for another. I understand that my assistant was following the standard policy but when another assistant treats another customer differently infront of another, I couldn't help but be unsatisfied with the service. As a customer with a mac book pro, mac book, 2 ipads, an iphone and as a business customer which uses and buys apple products on a day to day basis, this is not the service I have learned to expect.
I would like a reply from apple but cannot find an email address for either the store or apple in general