My button response improved tremendously when I removed my Invisible Shield screen protector and went with the cheaper kind from the Sprint store. I was having to press the back button a couple of times sometimes and also more firmly to get the screen to respond with the IS. The cheaper kind only covers the display screen and is a much thinner, smoother material, whereas the IS covers the entire glass front of the screen and is much thicker. I've noticed some people complaining about response of these buttons in the past and have wondered if any were using this protector.... it was that was definitely causing my issue. It wasn't a huge deal and I almost got used to it, but it works much better for me without it.