The iPhones 6s and 6s plus have an error in the battery indicator, since it can stop working and stop showing the real charge of the mobile.
This error, which appears when the device time is manually changed, has already been recognized by Apple, who indicates that it is working on the definitive solution, although an alternative has already been given: restart the mobile and activate automatic synchronization within Date and time, in the system settings.
The problem appears only on some phones that have manually changed the time, so it is not general. Even so, it is serious, since it can indicate that the mobile is at 50% battery, for example, when it is only at 5%, so the device can be turned off quickly, without prior notice.
Once again we see how the battery is still the main headache of mobile phone manufacturers. While the devices are becoming more powerful, older and with better screens, the batteries do not evolve at the same speed, leaving their autonomy reduced to a few hours. This problem causes users to always be aware of the existing level during the day, and if this level does not work properly, the problem worsens.