Apple engineers are purportedly contacting some iPhone 4S owners to try to solve problems with battery life on the new device, after some people have seen dramatic drops in longevity compared to previous models.

One owner has told “The Guardian” (http://macte.ch/3wvhN) that Apple contacted him directly and asked him to install a monitoring program on the phone to try to diagnose the problem, which is so far unexplained. In its data sheet for the iPhone 4S, which was released earlier this month, Apple quietly noted that the standby time for the new phone would only be 200 hours — compared to 300 for the iPhone 4, and 250 hours even for the original 2007 iPhone.

The company did not offer any reason when asked why by “The Guardian.” However, Apple did note that other lifespans such as 3G talktime were as long or longer than previous models.