I'm having a hard time using my iPhone 4 inside my office at work. The signal is very weak and when I can make a call it's usually dropped. I brought in my iPad and to my surprise the signal is the best you can get; therefore, I installed Skype, purchased unlimited calls to land and mobile lines, and also bought a Skype phone number and now use my iPad to make general calls. Whatever they did to the iPhone's antenna, well they screwed up really bad. For those you have both the iPhone 4 and iPad 3G, test it out.