Chosen Solution
My iPhone 5S boots up very slowly sometimes. When on the Apple logo, he stays there for some time. Sometimes he starts up normally, sometimes very slow. I also noticed that sometimes when on Apple logo he will reboot and start booting again. Weird, because sometimes everything goes normal, sometimes he starts up slow. I checked battery health via iBackupBot and battery still have 90% of original capacity. DFU restore has already been done..
Apple quietly changed the file system in iOS 10.3, it may be that the file system on your iPhone is corrupt. I would suggest the following: • backup your iphone completely in iTunes • grab the latest full iOS update from http://www.iclarified.com/750/where-to-d… • put your phone into DFU mode • in iTunes, it will ask to restore – in Windows hold shift and click Restore and select the firmware you just downloaded; in OS X hold Option and click the restore button and select the firmware you just downloaded • after the firmware finishes restoring to the iPhone, it will as you to restore from a backup – don’t – instead, set up as a new iPhone and follow the iphone through the new set up sequence • now, restore as from the backup you made in the first step.
