Apple claims that the iPhone 6S Plus will give you up to 12 hours of total usage. Other users have said that they are getting up to 11-12 hours! Some having 50% by the end of the day. Wheres my 11-12 hours? I only get up to 8 hours 30 minute total in a single charge (%20< i use low power mode.). My first iphone 6s plus have battery issue, apple changes it and gave me a new one. The new one is 3 weeks old. I don't have facebook app and heavy games. Last 2 weeks, i reset my iphone twice and set as a new. Every time i test it but same result. Please help me. I really want 11 hours of battery usage without having to worry about not having a charger with me. I use my phone a lot. :/ (background app refresh off, i have 3 mail account 2 gmail and 1 exchange, location services off, fitness off, some system services off)