iPhone: Battery life after a year sucks

Since I started using my iPad for most browsing and reading, I have noticed that my 9-month-old iPhone 3GS seems to be suffering rapid battery failure. I had been getting worried before the iPad came on the scene because the iPhone been in constant daily use for all sorts of work during those nine months. But now I see that even light usage depletes the battery alarmingly. The 50% battery level comes up during the morning and by mid afternoon I am having to boost the battery with my external Kensington unit. I now believe that the iPhone will need a new battery before it is one year old; I also suspect the iPad will also run out of steam within a year. It’s worrying because of the cost of replacement which, as we know, has to be done by Apple. At least we are told that the new iPhone’s battery will have a 16 percent increase in capacity. Unfortunately, though, the new features of iPhone OS 4, including multi-tasking, will do nothing to prolong battery life.