Based on these articles, it does not look like sweat and excercise are compatible with the iphone and its water sensors. Living in the south where it's 100% humidity all the time, this seems to trigger the sensor of some iphones also. That is not fair for iphone users who truly never had their phone touch water. The last link is a video. http://reviews.cnet.com/8301-19512_7-10214153-233.html?tag=TOCmoreStories.0 http://www.click2houston.com/news/19114407/detail.html#- http://www.click2houston.com/video/19112376/index.html If this has been posted already, I did a search and did not find it.