I have updated my iPhone 5S from 9.3iOS to 10.2iOS, so far so good, everything is smooth, battery is ok. however there are few things I noticed;
1. iMessage sending progress status is invisible, it only appears if sending takes time.
2. when I turn off the autorotate function, the assistive touch is hiding at the bottom of the screen when I flip the phone horizontally.
3. sometimes the assistive touch doesn’t response.
4. sometimes the battery percentage indicator jumps down 2-4% down instead of slowly 1% decremental.
5. sometimes the clock icon stops.
6. sometimes it is difficult to pickup signal compare to previous version.
.but, performance is improved a little.
.appearance is also ok