Since there were some reports regarding the draining of iPhone 6S battery Apple has updated the reason behind the issue on its Chine website. The message states that due to some batteries were exposed to "controlled ambient air" during manufacturing some users faced the problem – although scope of the affected customers can be more than what is expected. When it comes to battery back-up iPhone is considered on the front row. Earlier some consumers reported that their iPhone 6s facing unexpected shutdowns due to the battery issue. Apple said that smartphone made during September and October last year have this issue and the company is investigating to solve the problem by improving its algorithms. A small number of customers outside of the affected range have also reported an unexpected shutdown. Some of these shutdowns can occur under normal conditions in order for the iPhone to protect its electronics. In an effort to gather more information, we are including additional diagnostic capability in an iOS software update which will be available next week. This will allow us to gather information over the coming weeks which may potentially help us improve the algorithms used to manage battery performance and shutdown. If such improvements can be made, they will be delivered in future software updates. Apple is preparing new diagnostic tool for small number of affected customers, so the company can gather information and try to overcome battery shutdown problem in next iOS version. The updated version iOS 10.2 will become available in next week and Apple mentioned that if any improvements and solutions are discovered thanks to the diagnostic tool, "they will be delivered in future software updates." Apple is providing a facility to replace battery who think their iPhone 6s is affected who are facing the issue. Users by putting their serial number on a new tool can check if their phones come under replacement program.