I've read some articles regarding this topic, please allow me to share it here. The iPhone 4S sold numerous units on pre-orders and will continue to sell quickly. As with all brand new products, however, the 4S is facing a few bugs and bumps in the road. Some are pointing to possible coding bugs in iPhone 4S apps that could be draining the battery easily and completely. Resource for this article:
Apps on iPhone 4S could be worsening battery drain.