I´d like to open the discussion around the altitude issue again.
2 years ago I bought a brand new Iphone 5 from the Apple store. I live in Peru and work in mining. Peruvian mines are usually located in very high altitude places. Specifically the company I work for operates a mine located at 13,400 feet (4100 masl). Early this year I went to the mine and once I arrived I started using my phone and noticed that on the upper left corner there was a 1 mm gap through which I was able to see the backlight of the LCD screen. I thought I had broken my phone. The gap allowed me to insert fingernail in between the screen and the body of the phone.
When I returned back to sea level the issue disappeared. I thought the battery was swollen due to it being damaged and following the apple forum advice I took the phone to a qualified tech support company. They did not do anything to it nor offered me any alternative (thanks Apple for your poor service outside the US) so I took it to the hacker/pirate repair guys in a tech mall close by my office. They opened the phone and showed me that the plastic wrapper around the battery which is supposed to be tightly attached to the battery was inflated like a potato chip bag. They said that this wrapper inflates even more in the altitude and that all phones have the same issue but the seal around the screen is tight and flexible enough to withstand the pressure caused by the inflated battery. So my issue is actually not battery-related but screen seal-related.
If the seal gives up in a location lower than the volume buttons the screen will bend and even crack around that area. In my case it gave up in a corner where the screen can release the tension through the longer and smaller sides of the screen. This symptom is consistent with the descriptions made by several forum users regarding "spider web" like distortions and non-working areas of the touch screen at high altitudes that go away once the phone returns back to sea level. Since then I have replaced the battery with another that had the wrapper very tight around it and when I went up to the mine the issue re-occurred. Coincidentally a co-worker had the same model iphone I had but his did not showed the issue (I guess because of the seal)
So in conclusion, the high altitude issue is the consequence of the battery wrapper inflating like a balloon and a bad seal giving up. Apple design guys: find a way to allow the battery to release the pressure of the wrapper or assemble the battery in a low pressure environment so it is "used to" the low pressure from the get go. Also do a better job with the seal. I know the issue is not affecting a massive number of iphones for you to look into this but there are many of us that admire the brand and its products and are proud of showing them in harsh environments like the Peruvian highlands and it is a shame that we have to say that the Iphone got altitude sickness.
