I searched and didn't find anyone seeing this problem that I seem to be having (at least after looking at 8 pages of search results). At least once a day, when checking my mail (simple Yahoo account) on my iPhone 4 (iOS 4.0), the mail app locks up and just displays a blank white screen. I can press the home button and I can go to other apps, etc. and they will work fine, but when I go back to mail, all I see is the white screen. I reboot the phone and it's back to normal until it happens the next time. Before I do a clean restore and an upgrade, I'm just wondering if anyone else has seen this problem or has any suggestions. Thanks.